James P. Morken

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Name: Morken, James P.

Organization: Boston College , USA

Department: Department of Chemistry

Title: (PhD)

TOPICS

Organic Chemistry

suzuki-miyaura Coupling allene

Chemicals
References

Nickel-Catalyzed Enantioselective Conjunctive Cross-Coupling of 9-BBN Borates

Co-reporter:Matteo Chierchia;Chunyin Law; James P. Morken

Angewandte Chemie 2017 Volume 129(Issue 39) pp:12032-12036

Publication Date(Web):2017/09/18

DOI:10.1002/ange.201706719

AbstractCatalytic enantioselective conjunctive cross-coupling between 9-BBN borate complexes and aryl electrophiles can be accomplished with Ni salts in the presence of a chiral diamine ligand. The reactions furnish chiral 9-BBN derivatives in an enantioselective fashion and these are converted to chiral alcohols and amines, or engaged in other stereospecific C−C bond forming reactions.

A Boron Alkylidene–Alkene Cycloaddition Reaction: Application to the Synthesis of Aphanamal

Co-reporter:Xun Liu;T. Maxwell Deaton; Dr. Fredrik Haeffner; Dr. James P. Morken

Angewandte Chemie 2017 Volume 129(Issue 38) pp:11643-11647

Publication Date(Web):2017/09/11

DOI:10.1002/ange.201705720

AbstractWe describe an unusual net [2+2] cycloaddition reaction between boron alkylidenes and unactivated alkenes. This reaction provides a new method for the construction of carbocyclic ring systems bearing versatile organoboronic esters. Aside from surveying the scope of this reaction, we provide details about the mechanistic underpinnings of this process, and examine its application to the synthesis of the natural product aphanamal.

Nickel-Catalyzed Enantioselective Conjunctive Cross-Coupling of 9-BBN Borates

Co-reporter:Matteo Chierchia;Chunyin Law; James P. Morken

Angewandte Chemie International Edition 2017 Volume 56(Issue 39) pp:11870-11874

Publication Date(Web):2017/09/18

DOI:10.1002/anie.201706719

Nickel-Catalyzed Asymmetric Kumada Cross-Coupling of Symmetric Cyclic Sulfates

Co-reporter:Meredith S. Eno; Alexander Lu

Journal of the American Chemical Society 2016 Volume 138(Issue 25) pp:7824-7827

Publication Date(Web):June 8, 2016

DOI:10.1021/jacs.6b03384

Nickel-catalyzed enantioselective cross-couplings between symmetric cyclic sulfates and aromatic Grignard reagents are described. These reactions are effective with a broad range of substituted cyclic sulfates and deliver products with asymmetric tertiary carbon centers. Mechanistic experiments point to a stereoinvertive SN2-like oxidative addition of a nickel complex to the electrophilic substrate.

Carbohydrate-Catalyzed Enantioselective Alkene Diboration: Enhanced Reactivity of 1,2-Bonded Diboron Complexes

Co-reporter:Lichao Fang; Lu Yan; Fredrik Haeffner

Journal of the American Chemical Society 2016 Volume 138(Issue 8) pp:2508-2511

Publication Date(Web):February 8, 2016

DOI:10.1021/jacs.5b13174

Catalytic enantioselective diboration of alkenes is accomplished with readily available carbohydrate-derived catalysts. Mechanistic experiments suggest the intermediacy of 1,2-bonded diboronates.

Modular, Catalytic Enantioselective Construction of Quaternary Carbon Stereocenters by Sequential Cross-Coupling Reactions

Co-reporter:Bowman Potter, Emma K. Edelstein, and James P. Morken

Organic Letters 2016 Volume 18(Issue 13) pp:3286-3289

Publication Date(Web):June 16, 2016

DOI:10.1021/acs.orglett.6b01580

The catalytic Suzuki–Miyaura cross-coupling with chiral γ,γ-disubstituted allylboronates in the presence of RuPhos ligand occurs with high regioselectivity and enantiospecificity, furnishing nonracemic compounds with quaternary centers. Mechanistic experiments suggest that the reaction occurs by transmetalation with allyl migration, followed by rapid reductive elimination.

Catalytic conjunctive cross-coupling enabled by metal-induced metallate rearrangement

Co-reporter:Liang Zhang;Emma K. Edelstein;Adam A. Szymaniak;Gabriel J. Lovinger;Matteo P. Chierchia

Science 2016 Volume 351(Issue 6268) pp:70-74

Publication Date(Web):01 Jan 2016

DOI:10.1126/science.aad6080

A two-for-one twist on Suzuki coupling

The Suzuki-Miyaura coupling reaction is one of the most widely used ways of making carbon-carbon bonds. Essentially a palladium catalyst activates one carbon fragment and then links it to a second fragment pulled from boron. Zhang et al. now demonstrate a twist on the conventional pathway (see the Perspective by Fyfe and Watson). In their system, the palladium initially coaxes together two carbon fragments on one boron center. Then the catalyst stitches a second C-C bond to a third, external fragment. A chiral ligand renders the reaction highly enantio-selective.

Science, this issue p. 70; see also p. 26

Catalytic Enantioselective Functionalization of Unactivated Terminal Alkenes

Co-reporter:John R. Coombs ; James P. Morken

Angewandte Chemie International Edition 2016 Volume 55( Issue 8) pp:2636-2649

Publication Date(Web):

DOI:10.1002/anie.201507151

Abstract

Terminal alkenes are readily available functional groups which appear in α-olefins produced by the chemical industry, and they appear in the products of many contemporary synthetic reactions. While the organic transformations that apply to alkenes are amongst the most studied reactions in all of chemical synthesis, the number of reactions that apply to nonactivated terminal alkenes in a catalytic enantioselective fashion is small in number. This Minireview highlights the cases where stereocontrol in catalytic reactions of 1-alkenes is high enough to be useful for asymmetric synthesis.

Katalytische enantioselektive Funktionalisierung von nichtaktivierten terminalen Alkenen

Co-reporter:John R. Coombs ; James P. Morken

Angewandte Chemie 2016 Volume 128( Issue 8) pp:2682-2696

Publication Date(Web):

DOI:10.1002/ange.201507151

Abstract

Terminale Alkene sind leicht verfügbare Verbindungen, die in der chemischen Industrie in Form von α-Olefinen sowie als Produkte vieler gängiger Synthesereaktionen anfallen. Die organischen Transformationen solcher Alkene gehören zu den am besten untersuchten Reaktionen in der chemischen Synthese, allerdings kennt man nur relativ wenige Reaktionen, in denen nichtaktivierte terminale Alkene katalytisch und enantioselektiv umgesetzt werden. In diesem Kurzaufsatz stellen wir diejenigen Fälle vor, in denen die Stereokontrolle in katalytischen Reaktionen von 1-Alkenen ausreicht, um sie für asymmetrische Synthesen nutzbar zu machen.

Hydroxyl-Directed Cross-Coupling: A Scalable Synthesis of Debromohamigeran E and Other Targets of Interest

Co-reporter:Thomas P. Blaisdell

Journal of the American Chemical Society 2015 Volume 137(Issue 27) pp:8712-8715

Publication Date(Web):June 30, 2015

DOI:10.1021/jacs.5b05477

A hydroxyl functional group positioned β to a pinacol boronate can serve to direct palladium-catalyzed cross-coupling reactions. This feature can be used to control the reaction site in multiply borylated substrates and can activate boronates for reaction that would otherwise be unreactive.

Enantioselective Hydroformylation of 1-Alkenes with Commercial Ph-BPE Ligand

Co-reporter:Zhiyong Yu, Meredith S. Eno, Alexandra H. Annis, and James P. Morken

Organic Letters 2015 Volume 17(Issue 13) pp:3264-3267

Publication Date(Web):June 19, 2015

DOI:10.1021/acs.orglett.5b01421

A rhodium complex, in conjunction with commercially available Ph-BPE ligand, catalyzes the branch-selective asymmetric hydroformylation of 1-alkenes and rapidly generates α-chiral aldehydes. A wide range of terminal olefins including 1-dodecene were examined, and all delivered high enantioselectivity (up to 98:2 er) as well as good branch:linear ratios (up to 15:1).

Synthesis of Vinyl Boronates from Aldehydes by a Practical Boron–Wittig Reaction

Co-reporter:John R. Coombs, Liang Zhang, and James P. Morken

Organic Letters 2015 Volume 17(Issue 7) pp:1708-1711

Publication Date(Web):March 23, 2015

DOI:10.1021/acs.orglett.5b00480

A highly stereoselective boron-Wittig reaction between stable and readily accessible 1,1-bis(pinacolboronates) and aldehydes furnishes a variety of synthetically useful di- and trisubstituted vinyl boronate esters.

Branched/linear selectivity in palladium-catalyzed allyl-allyl cross-couplings: the role of ligands

Co-reporter:Michael J. Ardolino, James P. Morken

Tetrahedron 2015 Volume 71(Issue 37) pp:6409-6413

Publication Date(Web):16 September 2015

DOI:10.1016/j.tet.2015.05.015

While Pd-catalyzed allyl-allyl cross-couplings in the presence of small-bite-angle bidentate ligands reliably furnish the branched regioisomer with high levels of selectivity, cross-couplings in the presence of large-bite-angle bidentate ligands give varying, often unpredictable, levels of selectivity. In a combined computational and experimental study, we probe the underlying features that govern the regioselectivity in these metal-catalyzed cross-couplings.

Catalytic bismetallative multicomponent coupling reactions: scope, applications, and mechanisms

Co-reporter:Hee Yeon Cho and James P. Morken

Chemical Society Reviews 2014 vol. 43(Issue 13) pp:4368-4380

Publication Date(Web):16 Apr 2014

DOI:10.1039/C3CS60482A

Catalytic reactions have played an indispensable role in organic chemistry for the last several decades. In particular, catalytic multicomponent reactions have attracted significant attention due to their efficiency and expediency towards complex molecule synthesis. The presence of bismetallic reagents (e.g. B–B, Si–Si, B–Si, Si–Sn, etc.) in this process renders the products enriched with various functional groups and multiple stereocenters. For this reason, catalytic bismetallative coupling is considered an effective method to generate the functional and stereochemical complexity of simple hydrocarbon substrates. This review highlights key developments of transition-metal catalyzed bismetallative reactions involving multiple π components. Specifically, it will highlight the scope, synthetic applications, and proposed mechanistic pathways of this process.

A Catalytic Enantiotopic-Group-Selective Suzuki Reaction for the Construction of Chiral Organoboronates

Co-reporter:Chunrui Sun ; Bowman Potter

Journal of the American Chemical Society 2014 Volume 136(Issue 18) pp:6534-6537

Publication Date(Web):February 19, 2014

DOI:10.1021/ja500029w

Catalytic enantiotopic-group-selective cross-couplings of achiral geminal bis(pinacolboronates) provide a route for the construction of nonracemic chiral organoboronates. In the presence of a chiral monodentate taddol-derived phosphoramidite ligand, these reactions occur with high levels of asymmetric induction. Mechanistic experiments with chiral 10B-enriched geminal bis(boronates) suggest that the reaction occurs by a stereochemistry-determining transmetalation that occurs with inversion of configuration at carbon.

Congested C–C Bonds by Pd-Catalyzed Enantioselective Allyl–Allyl Cross-Coupling, a Mechanism-Guided Solution

Co-reporter:Michael J. Ardolino

Journal of the American Chemical Society 2014 Volume 136(Issue 19) pp:7092-7100

Publication Date(Web):April 10, 2014

DOI:10.1021/ja502280w

Under the influence of a chiral bidentate diphosphine ligand, the Pd-catalyzed asymmetric cross-coupling of allylboron reagents and allylic electrophiles establishes 1,5-dienes with adjacent stereocenters in high regio- and stereoselectivity. A mechanistic study of the coupling utilizing reaction calorimetry and density functional theory analysis suggests that the reaction operates through an inner-sphere 3,3′-reductive elimination pathway, which is both rate-defining and stereodefining. Coupled with optimized reaction conditions, this mechanistic detail is used to expand the scope of allyl–allyl couplings to allow the generation of 1,5-dienes with tertiary centers adjacent to quaternary centers as well as a unique set of cyclic structures.

Simple Access to Elusive α-Boryl Carbanions and Their Alkylation: An Umpolung Construction for Organic Synthesis

Co-reporter:Kai Hong ; Xun Liu

Journal of the American Chemical Society 2014 Volume 136(Issue 30) pp:10581-10584

Publication Date(Web):July 14, 2014

DOI:10.1021/ja505455z

The reaction of 1,1-bis(pinacolboronate) esters with alkyl halides can be effected by metal alkoxides and provides a strategy for the construction of organoboronate compounds. The reaction is found to occur by alkoxide-induced deborylation and generation of a boron-stabilized carbanion.

Nonracemic Allylic Boronates through Enantiotopic-Group-Selective Cross-Coupling of Geminal Bis(boronates) and Vinyl Halides

Co-reporter:Bowman Potter ; Adam A. Szymaniak ; Emma K. Edelstein

Journal of the American Chemical Society 2014 Volume 136(Issue 52) pp:17918-17921

Publication Date(Web):December 8, 2014

DOI:10.1021/ja510266x

Under the influence of a chiral palladium catalyst, 1,1-bis(pinacolboronate) esters undergo asymmetric cross-coupling with bromoalkenes to generate nonracemic allyl boronates with high levels of enantioselectivity. The so-formed allyl boronates may be oxidized with hydrogen peroxide to provide secondary allylic alcohols or with nitrosobenzene to furnish nonracemic tertiary allylic alcohols. Mechanistic experiments suggest the operation of a pathway involving outer-sphere stereoinvertive transmetalation.

Hydroxyl-Directed Stereoselective Diboration of Alkenes

Co-reporter:Thomas P. Blaisdell ; Thomas C. Caya ; Liang Zhang ; Amparo Sanz-Marco

Journal of the American Chemical Society 2014 Volume 136(Issue 26) pp:9264-9267

Publication Date(Web):June 18, 2014

DOI:10.1021/ja504228p

An alkoxide-catalyzed directed diboration of alkenyl alcohols is described. This reaction occurs in a stereoselective fashion and is demonstrated with cyclic and acyclic homoallylic and bishomoallylic alcohol substrates. After oxidation, the reaction generates 1,2-diols such that the process represents a method for the stereoselective directed dihydroxylation of alkenes.

Enantioselective Carbocycle Formation through Intramolecular Pd-Catalyzed Allyl–Aryl Cross-Coupling

Co-reporter:Christopher H. Schuster, John R. Coombs, Zachary A. Kasun, and James P. Morken

Organic Letters 2014 Volume 16(Issue 17) pp:4420-4423

Publication Date(Web):August 8, 2014

DOI:10.1021/ol5019163

Aryl electrophiles containing tethered allylboronate units undergo efficient intramolecular coupling in the presence of a chiral palladium catalyst to give enantioenriched carbocyclic products. The reaction is found to be quite general, affording 5, 6, and 7-membered carbocyclic products as single regioisomers and with moderate enantioselectivities. Examination of differential coupling partners points to rapid allyl-equilibration as a key stereodefining feature.

Catalytic Stereospecific Allyl–Allyl Cross-Coupling of Internal Allyl Electrophiles with AllylB(pin)

Co-reporter:Hai Le, Amanda Batten, and James P. Morken

Organic Letters 2014 Volume 16(Issue 8) pp:2096-2099

Publication Date(Web):April 4, 2014

DOI:10.1021/ol500456s

Application of internal electrophiles in catalytic stereospecific allyl–allyl cross-coupling enable the rapid construction of multisubstituted 1,5-dienes, including those with all carbon quaternary centers. Compounds with minimal steric differentiation can be synthesized with high enantiomeric excess.

Synthesis of (+)-Discodermolide by Catalytic Stereoselective Borylation Reactions

Co-reporter:Zhiyong Yu;Robert J. Ely ; James P. Morken

Angewandte Chemie International Edition 2014 Volume 53( Issue 36) pp:9632-9636

Publication Date(Web):

DOI:10.1002/anie.201405455

Abstract

The marine natural product (+)-discodermolide was first isolated in 1990 and, to this day, remains a compelling synthesis target. Not only does the compound possess fascinating biological activity, but it also presents an opportunity to test current methods for chemical synthesis and provides an inspiration for new reaction development. A new synthesis of discodermolide employs a previously undisclosed stereoselective catalytic diene hydroboration and also establishes a strategy for the alkylation of chiral enolates. Furthermore, this synthesis of discodermolide provides the first examples of the asymmetric 1,4-diboration of dienes and borylative diene–aldehyde couplings in complex-molecule synthesis.

Synthesis of (+)-Discodermolide by Catalytic Stereoselective Borylation Reactions

Co-reporter:Zhiyong Yu;Robert J. Ely ; James P. Morken

Angewandte Chemie 2014 Volume 126( Issue 36) pp:9786-9790

Publication Date(Web):

DOI:10.1002/ange.201405455

Abstract

Catalytic Enantioselective One-pot Aminoborylation of Aldehydes: A Strategy for Construction of Nonracemic α-Amino Boronates

Co-reporter:Kai Hong

Journal of the American Chemical Society 2013 Volume 135(Issue 25) pp:9252-9254

Publication Date(Web):June 13, 2013

DOI:10.1021/ja402569j

We report a strategy for the conversion of aldehydes to enantiomerically enriched α-amino boronates through the intermediacy of in situ-generated silylimines. This transformation is brought about by Pt-catalyzed asymmetric addition of B2(pin)2 across the imine double bond. An attractive feature of the intermediate diboration adduct is that it can be acylated directly and provides convenient access to important N-acyl α-amino boronic ester derivatives.

Scope and Mechanism of the Pt-Catalyzed Enantioselective Diboration of Monosubstituted Alkenes

Co-reporter:John R. Coombs ; Fredrik Haeffner ; Laura T. Kliman

Journal of the American Chemical Society 2013 Volume 135(Issue 30) pp:11222-11231

Publication Date(Web):July 18, 2013

DOI:10.1021/ja4041016

The Pt-catalyzed enantioselective diboration of terminal alkenes can be accomplished in an enantioselective fashion in the presence of chiral phosphonite ligands. Optimal procedures and the substrate scope of this transformation are fully investigated. Reaction progress kinetic analysis and kinetic isotope effects suggest that the stereodefining step in the catalytic cycle is olefin migratory insertion into a Pt–B bond. Density functional theory analysis, combined with other experimental data, suggests that the insertion reaction positions platinum at the internal carbon of the substrate. A stereochemical model for this reaction is advanced that is in line both with these features and with the crystal structure of a Pt–ligand complex.

A Catalytic Enantioselective Tandem Allylation Strategy for Rapid Terpene Construction: Application to the Synthesis of Pumilaside Aglycon

Co-reporter:Grace E. Ferris ; Kai Hong ; Ian A. Roundtree

Journal of the American Chemical Society 2013 Volume 135(Issue 7) pp:2501-2504

Publication Date(Web):February 7, 2013

DOI:10.1021/ja400506j

Catalytic enantioselective 1,2-diboration of 1,3-dienes followed by cascade allylborations with dicarbonyls provides rapid entry into carbocyclic reaction products. The stereochemical course of this reaction was studied along with its application in the synthesis of pumilaside aglycon.

Catalytic Enantioselective Allyl–Allyl Cross-Coupling with a Borylated Allylboronate

Co-reporter:Hai Le, Robert E. Kyne, Laura A. Brozek, and James P. Morken

Organic Letters 2013 Volume 15(Issue 7) pp:1432-1435

Publication Date(Web):March 19, 2013

DOI:10.1021/ol400088g

Catalytic enantioselective allyl–allyl cross-coupling of a borylated allylboronate reagent gives versatile borylated chiral 1,5-hexadienes. These compounds may be manipulated in a number of useful ways to give functionalized chiral building blocks for asymmetric synthesis.

Stereocontrol in Palladium-Catalyzed Propargylic Substitutions: Kinetic Resolution to give Enantioenriched 1,5-Enynes and Propargyl Acetates

Co-reporter:Michael J. Ardolino;Meredith S. Eno

Advanced Synthesis & Catalysis 2013 Volume 355( Issue 17) pp:3413-3419

Publication Date(Web):

DOI:10.1002/adsc.201300720

Direct Stereospecific Amination of Alkyl and Aryl Pinacol Boronates

Co-reporter:Scott N. Mlynarski ; Alexander S. Karns

Journal of the American Chemical Society 2012 Volume 134(Issue 40) pp:16449-16451

Publication Date(Web):September 24, 2012

DOI:10.1021/ja305448w

The direct amination of alkyl and aryl pinacol boronates is accomplished with lithiated methoxyamine. This reaction directly provides aliphatic and aromatic amines, stereospecifically, and without preactivation of the boronate substrate.

Construction of 1,5-Enynes by Stereospecific Pd-Catalyzed Allyl–Propargyl Cross-Couplings

Co-reporter:Michael J. Ardolino

Journal of the American Chemical Society 2012 Volume 134(Issue 21) pp:8770-8773

Publication Date(Web):May 17, 2012

DOI:10.1021/ja302329f

The palladium-catalyzed cross-coupling of chiral propargyl acetates and allyl boronates delivers chiral 1,5-enynes with excellent levels of chirality transfer and can be applied across a broad range of substrates.

Ni- and Pd-Catalyzed Synthesis of Substituted and Functionalized Allylic Boronates

Co-reporter:Ping Zhang, Ian A. Roundtree, and James P. Morken

Organic Letters 2012 Volume 14(Issue 6) pp:1416-1419

Publication Date(Web):February 29, 2012

DOI:10.1021/ol3001552

Two highly efficient and convenient methods for the synthesis of functionalized and substituted allylic boronates are described. In one procedure, readily available allylic acetates are converted to allylic boronates catalyzed by Ni/PCy3 or Ni/PPh3 complexes with high levels of stereoselectivity and in good yields. Alternatively, the borylation can be accomplished with commercially available Pd catalysts [e.g., Pd2(dba)3, PdCl2, Pd/C], starting with easily accessed allylic halides.

Catalytic Enantioselective 1,2-Diboration of 1,3-Dienes: Versatile Reagents for Stereoselective Allylation

Co-reporter:Laura T. Kliman;Scott N. Mlynarski;Grace E. Ferris ;Dr. James P. Morken

Angewandte Chemie International Edition 2012 Volume 51( Issue 2) pp:521-524

Publication Date(Web):

DOI:10.1002/anie.201105716

Catalytic Enantioselective 1,2-Diboration of 1,3-Dienes: Versatile Reagents for Stereoselective Allylation

Co-reporter:Laura T. Kliman;Scott N. Mlynarski;Grace E. Ferris ;Dr. James P. Morken

Angewandte Chemie 2012 Volume 124( Issue 2) pp:536-539

Publication Date(Web):

DOI:10.1002/ange.201105716

Enantioselective Construction of All-Carbon Quaternary Centers by Branch-Selective Pd-Catalyzed Allyl–Allyl Cross-Coupling

Co-reporter:Ping Zhang ; Hai Le ; Robert E. Kyne

Journal of the American Chemical Society 2011 Volume 133(Issue 25) pp:9716-9719

Publication Date(Web):June 7, 2011

DOI:10.1021/ja2039248

The Pd-catalyzed cross-coupling of racemic tertiary allylic carbonates and allylboronates is described. This reaction generates all-carbon quaternary centers in a highly regioselective and enantioselective fashion. The outcome of these reactions is consistent with a process that proceeds by way of 3,3′-reductive elimination of bis(η1-allyl)palladium intermediates. Strategies for distinguishing the product alkenes and application to the synthesis of (+)-α-cuparenone are also described.

Diastereocontrol in Asymmetric Allyl–Allyl Cross-Coupling: Stereocontrolled Reaction of Prochiral Allylboronates with Prochiral Allyl Chlorides

Co-reporter:Laura A. Brozek ; Michael J. Ardolino

Journal of the American Chemical Society 2011 Volume 133(Issue 42) pp:16778-16781

Publication Date(Web):October 5, 2011

DOI:10.1021/ja2075967

Palladium-catalyzed allyl–allyl cross-coupling was investigated with substituted prochiral allylic boronates. These reactions deliver products bearing adjacent stereocenters, and the issue of diastereocontrol is therefore paramount. Under appropriately modified conditions, this allyl–allyl coupling strategy was found to apply to a range of substrates, generally occurring with high enantioselectivity (92:8 to >99:1 er) and good diastereoselection (4:1 to 14:1 dr).

Catalytic Enantioselective Conjugate Allylation of Unsaturated Methylidene Ketones

Co-reporter:Laura A. Brozek, Joshua D. Sieber, and James P. Morken

Organic Letters 2011 Volume 13(Issue 5) pp:995-997

Publication Date(Web):February 2, 2011

DOI:10.1021/ol102982b

The use of unsaturated methylidene ketones in catalytic conjugate allylations allows a significant expansion in substrate scope and, with appropriate chiral ligands, occurs in a highly enantioselective fashion.

Modular Monodentate Oxaphospholane Ligands: Utility in Highly Efficient and Enantioselective 1,4-Diboration of 1,3-Dienes

Co-reporter:Christopher H. Schuster;Dr. Bo Li ;Dr. James P. Morken

Angewandte Chemie 2011 Volume 123( Issue 34) pp:8052-8055

Publication Date(Web):

DOI:10.1002/ange.201102404

A Boron-Based Synthesis of the Natural Product (+)-trans-Dihydrolycoricidine

Co-reporter:Dr. Sarah L. Poe ;Dr. James P. Morken

Angewandte Chemie 2011 Volume 123( Issue 18) pp:4275-4278

Publication Date(Web):

DOI:10.1002/ange.201007135

Modular Monodentate Oxaphospholane Ligands: Utility in Highly Efficient and Enantioselective 1,4-Diboration of 1,3-Dienes

Co-reporter:Christopher H. Schuster;Dr. Bo Li ;Dr. James P. Morken

Angewandte Chemie International Edition 2011 Volume 50( Issue 34) pp:7906-7909

Publication Date(Web):

DOI:10.1002/anie.201102404

A Boron-Based Synthesis of the Natural Product (+)-trans-Dihydrolycoricidine

Co-reporter:Dr. Sarah L. Poe ;Dr. James P. Morken

Angewandte Chemie International Edition 2011 Volume 50( Issue 18) pp:4189-4192

Publication Date(Web):

DOI:10.1002/anie.201007135

Catalytic Enantioselective Diboration of Cyclic Dienes. A Modified Ligand with General Utility

Co-reporter:Kai Hong and James P. Morken

The Journal of Organic Chemistry 2011 Volume 76(Issue 21) pp:9102-9108

Publication Date(Web):September 20, 2011

DOI:10.1021/jo201321k

The enantioselective 1,4-diboration of cyclic dienes with a new taddol-derived phosphonite ligand occurs with excellent enantioselectivity. Oxidation delivers the derived 1,4-diol, whereas homologation can be used to deliver a chiral 1,6-diol.

Pd-Catalyzed Enantioselective Allyl−Allyl Cross-Coupling

Co-reporter:Ping Zhang ; Laura A. Brozek

Journal of the American Chemical Society 2010 Volume 132(Issue 31) pp:10686-10688

Publication Date(Web):July 15, 2010

DOI:10.1021/ja105161f

The Pd-catalyzed cross-coupling of allylic carbonates and allylB(pin) is described. The regioselectivity of this reaction is sensitive to the bite angle of the ligand, with small-bite-angle ligands favoring the branched substitution product. This mode of regioselection is consistent with a reaction that operates by a 3,3′ reductive elimination reaction. In the presence of appropriate chiral ligands, this reaction is rendered enantioselective and applies to both aromatic and aliphatic allylic carbonates.

Ni-Catalyzed Borylative Diene−Aldehyde Coupling: The Remarkable Effect of P(SiMe3)3

Co-reporter:Hee Yeon Cho

Journal of the American Chemical Society 2010 Volume 132(Issue 22) pp:7576-7577

Publication Date(Web):May 18, 2010

DOI:10.1021/ja101513d

The nickel-catalyzed reaction of carbonyls and dienes was accomplished in a regio- and stereoselective fashion employing a stoichiometric amount of bis(pinacolato)diboron. In the presence of P(SiMe3)3, this reductive coupling furnishes allyl boronic esters which are regioisomeric to those obtained with PCy3 as the ligand. The coupling product may be subject to oxidation, which furnishes the derived 1,3-diol, or allylation with an additional aldehyde, which furnishes the derived 1,6-diol in a stereoselective fashion.

Regio- and Stereoselective Ni-Catalyzed 1,4-Hydroboration of 1,3-Dienes: Access to Stereodefined (Z)-Allylboron Reagents and Derived Allylic Alcohols

Co-reporter:Robert J. Ely

Journal of the American Chemical Society 2010 Volume 132(Issue 8) pp:2534-2535

Publication Date(Web):February 5, 2010

DOI:10.1021/ja910750b

A catalytic regio- and stereoselective 1,4-hydroboration of 1,3-dienes was accomplished with pinacolborane in the presence of Ni(cod)2 and PCy3. This reaction exhibits broad substrate scope operating on a range of substituted dienes and occurs with generally high levels of selectivity and efficiency. Reactivity patterns suggest that the reactive conformation of the diene is the S-cis form. The intermediate allylboronate can be oxidized to stereodefined allylic alcohols or can be used in stereoselective carbonyl addition reactions.

Enantioselective Synthesis of (−)-Sclerophytin A by a Stereoconvergent Epoxide Hydrolysis

Co-reporter:Bin Wang ; Armando P. Ramirez ; Justin J. Slade

Journal of the American Chemical Society 2010 Volume 132(Issue 46) pp:16380-16382

Publication Date(Web):October 28, 2010

DOI:10.1021/ja108185z

The cytotoxic natural product (−)-sclerophytin A was constructed in 13 steps from geranial. Highlights from the synthesis are a stereoselective Oshima−Utimoto reaction, a Shibata−Baba indium-promoted radical cyclization, and a novel stereoconvergent epoxide hydrolysis.

Allylation of Nitrosobenzene with Pinacol Allylboronates. A Regioselective Complement to Peroxide Oxidation

Co-reporter:Robert E. Kyne, Michael C. Ryan, Laura T. Kliman and James P. Morken

Organic Letters 2010 Volume 12(Issue 17) pp:3796-3799

Publication Date(Web):August 5, 2010

DOI:10.1021/ol101472k

Addition of nitrosobenzene to pinacol allylboronates leads to oxidation of the organoboron with concomitant rearrangement of the substrate alkene. This reaction appears to proceed by allylboration of the nitroso group in analogy to carbonyl and imine allylation reactions. Remarkably, the N−O bond is cleaved during the reaction such that simple alcohols are the final reaction product.

Pd-Catalyzed Carbonylative Conjugate Addition of Dialkylzinc Reagents to Unsaturated Carbonyls

Co-reporter:Daniel W. Custar, Hai Le and James P. Morken

Organic Letters 2010 Volume 12(Issue 17) pp:3760-3763

Publication Date(Web):August 5, 2010

DOI:10.1021/ol1013476

The Pd-catalyzed addition of organozinc reagents to unsaturated carbonyls in the presence of carbon monoxide provides 1,4-diketones in good yield. The reaction was studied with a number of substituted cyclic and acyclic ketones as well as α,β-unsaturated aldehydes.

Ni(0)-Catalyzed 1,4-Selective Diboration of Conjugated Dienes

Co-reporter:Robert J. Ely and James P. Morken

Organic Letters 2010 Volume 12(Issue 19) pp:4348-4351

Publication Date(Web):September 9, 2010

DOI:10.1021/ol101797f

A catalytic stereoselective 1,4-diboration of conjugated dienes with B2(pin)2 was accomplished with Ni(cod)2 and PCy3 as the catalyst. This reaction broadens the substrate scope of current methods for catalytic diene diboration by including internal and sterically hindered dienes, and it proceeds efficiently at low catalyst loadings. The intermediate allylboronate was oxidized to the stereodefined allylic 1,4-diol.

Asymmetric 1,4-Dihydroxylation of 1,3-Dienes by Catalytic Enantioselective Diboration

Co-reporter:Heather E. Burks ; Laura T. Kliman

Journal of the American Chemical Society 2009 Volume 131(Issue 26) pp:9134-9135

Publication Date(Web):June 8, 2009

DOI:10.1021/ja809610h

Asymmetric 1,4-dihydroxylations of 1,3-dienes, and other transformations, are initiated by the Pt-catalyzed enantioselective addition of bis(pinacolato)diboron (B2(pin)2) to conjugated dienes. The studies reported in this communication suggest that both cyclic and acyclic substrates will participate in this reaction; however, dienes which are unable to adopt the S-cis conformation are unreactive. For most substrates, 1,4-addition is the predominant pathway. In addition to oxidation to the derived 2-buten-1,4-diol, stereoselective carbonyl allylation with the intermediate bis(boronate) ester is also described.

Catalytic Enantioselective Allylation of Dienals through the Intermediacy of Unsaturated π-Allyl Complexes

Co-reporter:Ping Zhang

Journal of the American Chemical Society 2009 Volume 131(Issue 35) pp:12550-12551

Publication Date(Web):August 13, 2009

DOI:10.1021/ja9058537

The nickel-catalyzed enantioselective addition of allylboronic acid pinacol ester [allylB(pin)] to α,β,γ,δ-unsaturated aldehydes is described. This reaction results in a remarkable inversion of substrate olefin geometry, providing the Z,E-configured reaction product in good enantioselectivity and olefin stereoselectivity. The reaction appears to proceed by conversion of the dienal to an unsaturated π-allyl complex followed by reductive elimination via transition state II. Enantioselectivities range from 73−94% ee for a range of δ-substituted dienals when chiral ligand L3 is employed.

Pt-Catalyzed Enantioselective Diboration of Terminal Alkenes with B2(pin)2

Co-reporter:Laura T. Kliman ; Scott N. Mlynarski

Journal of the American Chemical Society 2009 Volume 131(Issue 37) pp:13210-13211

Publication Date(Web):August 25, 2009

DOI:10.1021/ja9047762

The Pt-catalyzed enantioselective addition of bis(pinacolato)diboron to simple monosubstituted alkenes is described. This reaction occurs in the presence of a readily available chiral phosphonite ligand and is effective with a variety of terminal alkene substrates. Importantly, the reaction can operate with catalyst loadings of only 1 mol % Pt. While oxidation of the intermediate 1,2-bis(boronate) ester provides the chiral 1,2-diol as the reaction product, the intermediate may also be subjected to homologation/oxidation to furnish a chiral 1,4-diol as the reaction product.

Catalytic enantioselective diboration, disilation and silaboration: new opportunities for asymmetric synthesis

Co-reporter:Heather E. Burks and James P. Morken

Chemical Communications 2007 (Issue 45) pp:4717-4725

Publication Date(Web):22 Aug 2007

DOI:10.1039/B707779C

This article summarizes recent developments in the area of catalytic enantioselective reactions of unsaturated organic substrates with diboron, silylboron, and disilane reagents. These reactions provide new routes to the functionalization of prochiral substrates and therefore offer new strategies in asymmetric organic synthesis.

Enantiomerically Enriched Tris(boronates): Readily Accessible Conjunctive Reagents for Asymmetric Synthesis

Co-reporter:John R. Coombs ; Liang Zhang

Journal of the American Chemical Society () pp:

Publication Date(Web):November 3, 2014

DOI:10.1021/ja510081r

The catalytic enantioselective diboration of vinyl boronate esters furnishes chiral tris(boronates) in a selective fashion. Subsequent deborylative alkylation occurs in a diastereoselective fashion, both for intermolecular and intramolecular processes.

Catalytic enantioselective diboration, disilation and silaboration: new opportunities for asymmetric synthesis

Co-reporter:Heather E. Burks and James P. Morken

Chemical Communications 2007(Issue 45) pp:NaN4725-4725

Publication Date(Web):2007/08/22

DOI:10.1039/B707779C

Catalytic bismetallative multicomponent coupling reactions: scope, applications, and mechanisms

Co-reporter:Hee Yeon Cho and James P. Morken

Chemical Society Reviews 2014 - vol. 43(Issue 13) pp:NaN4380-4380

Publication Date(Web):2014/04/16

DOI:10.1039/C3CS60482A