Co-reporter:Tomoya Miura, Junki Nakahashi, Wang Zhou, Yota Shiratori, Scott G. Stewart, and Masahiro Murakami
Journal of the American Chemical Society August 9, 2017 Volume 139(Issue 31) pp:10903-10903
Publication Date(Web):July 14, 2017
DOI:10.1021/jacs.7b06408
A cationic ruthenium(II) complex catalyzes double-bond transposition of 1,1-di(boryl)alk-3-enes to generate in situ 1,1-di(boryl)alk-2-enes, which then undergo chiral phosphoric acid catalyzed allylation of aldehydes producing homoallylic alcohols with a (Z)-vinylboronate moiety. 1,2-Anti stereochemistry is installed in an enantioselective manner. The (Z)-geometry forged in the products allows their isolation in a form of 1,2-oxaborinan-3-enes, upon which further synthetic transformations are operated.
Co-reporter:Dr. Tomoya Miura;Qiang Zhao; Dr. Masahiro Murakami
Angewandte Chemie 2017 Volume 129(Issue 52) pp:16872-16876
Publication Date(Web):2017/12/22
DOI:10.1002/ange.201709384
AbstractA rhodium(II)-catalyzed reaction of newly prepared 4-acyl-1-sulfonyl-1,2,3-triazoles with benzene, and its derivatives, is investigated. Acceptor/acceptor carbenoids generated from 4-acyltriazoles undergo selective insertion at aromatic C(sp2)−H bonds in the presence of benzylic C(sp3)−H bonds to produce N-sulfonylenaminones.
Co-reporter:Dr. Tomoya Miura;Qiang Zhao; Dr. Masahiro Murakami
Angewandte Chemie International Edition 2017 Volume 56(Issue 52) pp:16645-16649
Publication Date(Web):2017/12/22
DOI:10.1002/anie.201709384
AbstractA rhodium(II)-catalyzed reaction of newly prepared 4-acyl-1-sulfonyl-1,2,3-triazoles with benzene, and its derivatives, is investigated. Acceptor/acceptor carbenoids generated from 4-acyltriazoles undergo selective insertion at aromatic C(sp2)−H bonds in the presence of benzylic C(sp3)−H bonds to produce N-sulfonylenaminones.
Co-reporter:Dr. Tomoya Miura;Junki Nakahashi; Dr. Masahiro Murakami
Angewandte Chemie International Edition 2017 Volume 56(Issue 24) pp:6989-6993
Publication Date(Web):2017/06/06
DOI:10.1002/anie.201702611
Abstract(E)-δ-Boryl-substituted anti-homoallylic alcohols are synthesized in a highly diastereo- and enantioselective manner from 1,1-di(boryl)alk-3-enes and aldehydes. Mechanistically, the reaction consists of 1) palladium-catalyzed double-bond transposition of the 1,1-di(boryl)alk-3-enes to 1,1-di(boryl)alk-2-enes, 2) chiral phosphoric acid catalyzed allylation of aldehydes, and 3) palladium-catalyzed geometrical isomerization from the Z to E isomer. As a result, the configurations of two chiral centers and one double bond are all controlled with high selectivity in a single reaction vessel.
Co-reporter:Dr. Tomoya Miura;Junki Nakahashi; Dr. Masahiro Murakami
Angewandte Chemie 2017 Volume 129(Issue 24) pp:7093-7097
Publication Date(Web):2017/06/06
DOI:10.1002/ange.201702611
Abstract(E)-δ-Boryl-substituted anti-homoallylic alcohols are synthesized in a highly diastereo- and enantioselective manner from 1,1-di(boryl)alk-3-enes and aldehydes. Mechanistically, the reaction consists of 1) palladium-catalyzed double-bond transposition of the 1,1-di(boryl)alk-3-enes to 1,1-di(boryl)alk-2-enes, 2) chiral phosphoric acid catalyzed allylation of aldehydes, and 3) palladium-catalyzed geometrical isomerization from the Z to E isomer. As a result, the configurations of two chiral centers and one double bond are all controlled with high selectivity in a single reaction vessel.
Co-reporter:Yuuta Funakoshi, Tomoya MiuraMasahiro Murakami
Organic Letters 2016 Volume 18(Issue 24) pp:6284-6287
Publication Date(Web):November 28, 2016
DOI:10.1021/acs.orglett.6b03143
A rhodium(II)-catalyzed reaction of N-sulfonyl-1,2,3-triazoles with 2-(siloxy)furans is reported. Either open-chain penta-2,4-dien-1-imines or cyclic 1,2-dihydropyridines are selectively obtained depending on the ligand on rhodium(II).
Co-reporter:Dr. Tomoya Miura;Takayuki Nakamuro;Sho Miyakawa ;Dr. Masahiro Murakami
Angewandte Chemie 2016 Volume 128( Issue 30) pp:8874-8877
Publication Date(Web):
DOI:10.1002/ange.201603270
Abstract
A syn-selective aza-aldol reaction of boron aza-enolates, generated from N-sulfonyl-1,2,3-triazoles and 9-BBN-H, is reported. It provides a sequential one-pot procedure for the stereoselective construction of 1,3-amino alcohols, having contiguous stereocenters, starting from terminal alkynes.
Co-reporter:Dr. Tomoya Miura;Takayuki Nakamuro;Sho Miyakawa ;Dr. Masahiro Murakami
Angewandte Chemie International Edition 2016 Volume 55( Issue 30) pp:8732-8735
Publication Date(Web):
DOI:10.1002/anie.201603270
Abstract
A syn-selective aza-aldol reaction of boron aza-enolates, generated from N-sulfonyl-1,2,3-triazoles and 9-BBN-H, is reported. It provides a sequential one-pot procedure for the stereoselective construction of 1,3-amino alcohols, having contiguous stereocenters, starting from terminal alkynes.
Co-reporter:Tomoya Miura, Yuuta Funakoshi, Yoshikazu Fujimoto, Junki Nakahashi, and Masahiro Murakami
Organic Letters 2015 Volume 17(Issue 10) pp:2454-2457
Publication Date(Web):April 30, 2015
DOI:10.1021/acs.orglett.5b00960
A sequential procedure for the synthesis of 2,5-disubstituted thiazoles from terminal alkynes, sulfonyl azides, and thionoesters is reported. A copper(I)-catalyzed 1,3-dipolar cycloaddition of terminal alkynes with sulfonyl azides affords 1-sulfonyl-1,2,3-triazoles, which then react with thionoesters in the presence of a rhodium(II) catalyst. The resulting 3-sulfonyl-4-thiazolines subsequently aromatize into the corresponding 2,5-disubstituted thiazoles by elimination of the sulfonyl group.
Co-reporter:Dr. Tomoya Miura;Yoshikazu Fujimoto;Yuuta Funakoshi ;Dr. Masahiro Murakami
Angewandte Chemie International Edition 2015 Volume 54( Issue 34) pp:9967-9970
Publication Date(Web):
DOI:10.1002/anie.201504013
Abstract
N-Sulfonyl-1,2,3-triazoles react with thioesters in the presence of a rhodium(II) catalyst to produce β-sulfanyl enamides in a stereoselective manner. The reaction proceeds through generation of an α-imino rhodium carbene complex, nucleophilic addition of the sulfur atom of a thioester onto the carbenoid carbon atom, and subsequent intramolecular migration of the acyl group from the sulfur atom to the imino nitrogen atom. The method is successfully applied to a ring-expansion reaction of thiolactones, thus leading to the formation of sulfur-containing lactams.
Co-reporter:Dr. Tomoya Miura;Yoshikazu Fujimoto;Yuuta Funakoshi ;Dr. Masahiro Murakami
Angewandte Chemie 2015 Volume 127( Issue 34) pp:10105-10108
Publication Date(Web):
DOI:10.1002/ange.201504013
Abstract
N-Sulfonyl-1,2,3-triazoles react with thioesters in the presence of a rhodium(II) catalyst to produce β-sulfanyl enamides in a stereoselective manner. The reaction proceeds through generation of an α-imino rhodium carbene complex, nucleophilic addition of the sulfur atom of a thioester onto the carbenoid carbon atom, and subsequent intramolecular migration of the acyl group from the sulfur atom to the imino nitrogen atom. The method is successfully applied to a ring-expansion reaction of thiolactones, thus leading to the formation of sulfur-containing lactams.
Co-reporter:Dr. Masao Morimoto;Dr. Tomoya Miura;Dr. Masahiro Murakami
Angewandte Chemie 2015 Volume 127( Issue 43) pp:12850-12854
Publication Date(Web):
DOI:10.1002/ange.201506328
Abstract
Aliphatic terminal alkenes react with pinacolborane at ambient temperature to afford dehydrogenative borylation compounds as the major product when iPr-Foxap is used as the ligand with cationic rhodium(I) in the presence of norbornene, which acts as the sacrificial hydrogen acceptor. The reaction is applied to the one-pot syntheses of aldehydes and homoallylic alcohols from aliphatic terminal alkenes.
Co-reporter:Dr. Masao Morimoto;Dr. Tomoya Miura;Dr. Masahiro Murakami
Angewandte Chemie International Edition 2015 Volume 54( Issue 43) pp:12659-12663
Publication Date(Web):
DOI:10.1002/anie.201506328
Abstract
Aliphatic terminal alkenes react with pinacolborane at ambient temperature to afford dehydrogenative borylation compounds as the major product when iPr-Foxap is used as the ligand with cationic rhodium(I) in the presence of norbornene, which acts as the sacrificial hydrogen acceptor. The reaction is applied to the one-pot syntheses of aldehydes and homoallylic alcohols from aliphatic terminal alkenes.
Co-reporter:Tomoya Miura ; Takayuki Nakamuro ; Chia-Jung Liang ;Masahiro Murakami
Journal of the American Chemical Society 2014 Volume 136(Issue 45) pp:15905-15908
Publication Date(Web):October 22, 2014
DOI:10.1021/ja5096045
An efficient one-pot two-step procedure for asymmetric synthesis of piperidine-fused trans-cycloalkenes is reported. The method comprises the initial enantioselective installation of another cyclopropane ring onto methylenecyclopropanes and the subsequent thermal skeletal rearrangement in which the installed and inherent cyclopropane rings are both opened. A concerted mechanism is proposed for the latter thermal rearrangement reaction together with a closed transition state model.
Co-reporter:Tomoya Miura ; Yui Nishida ;Masahiro Murakami
Journal of the American Chemical Society 2014 Volume 136(Issue 17) pp:6223-6226
Publication Date(Web):April 15, 2014
DOI:10.1021/ja502169d
A cationic rhodium(I) catalyst turns 2-silyl-1-alkenylboronate, readily prepared from a terminal alkyne, into the corresponding allylboronate species, which immediately undergoes nucleophilic addition to an aldehyde to give a syn-homoallylic alcohol stereoselectively.
Co-reporter:Tomoya Miura ; Yuuta Funakoshi ;Masahiro Murakami
Journal of the American Chemical Society 2014 Volume 136(Issue 6) pp:2272-2275
Publication Date(Web):January 17, 2014
DOI:10.1021/ja412663a
The rhodium-catalyzed dearomatizing [3 + 2] annulation reaction of 4-(3-arylpropyl)-1,2,3-triazoles is described. It provides a straightforward synthetic pathway from simple 5-aryl-1-alkynes leading to tricyclic 3,4-fused dihydroindoles via the corresponding 1,2,3-triazoles.
Co-reporter:Tomoya Miura, Yuuta Funakoshi, Takamasa Tanaka, and Masahiro Murakami
Organic Letters 2014 Volume 16(Issue 10) pp:2760-2763
Publication Date(Web):April 28, 2014
DOI:10.1021/ol5010774
A rhodium-catalyzed reaction of formamides with N-sulfonyl-1,2,3-triazoles is developed to formulate a new one-pot procedure for the direct synthesis of α-amino enaminones from terminal alkynes.
Co-reporter:Tomoya Miura, Takayuki Nakamuro, Kentaro Hiraga and Masahiro Murakami
Chemical Communications 2014 vol. 50(Issue 72) pp:10474-10477
Publication Date(Web):18 Jul 2014
DOI:10.1039/C4CC04786A
A new procedure for the stereoselective synthesis of syn α-amino β-oxy ketones is reported. It consists of two steps; in the first step, α-amino silyl enol ethers having a (Z) geometry are prepared from 1-alkynes via 1-sulfonyl-1,2,3-triazoles. In the second step, the silyl enol ethers undergo the TiCl4-mediated Mukaiyama aldol reaction with aldehydes to produce α-amino β-oxy ketones with excellent syn-selectivity.
Co-reporter:Dr. Tomoya Miura;Takamasa Tanaka;Kohei Matsumoto ;Dr. Masahiro Murakami
Chemistry - A European Journal 2014 Volume 20( Issue 49) pp:16078-16082
Publication Date(Web):
DOI:10.1002/chem.201405357
Abstract
Relay actions of copper, rhodium, and gold formulate a one-pot multistep pathway, which directly gives 2,5-dihydropyrroles starting from terminal alkynes, sulfonyl azides, and propargylic alcohols. Initially, copper-catalyzed 1,3-dipolar cycloaddition of terminal alkynes with sulfonyl azides affords 1-sulfonyl-1,2,3-triazoles, which then react with propargylic alcohols under the catalysis of rhodium. The resulting alkenyl propargyl ethers subsequently undergo the thermal Claisen rearrangement to give α-allenyl-α-amino ketones. Finally, a gold catalyst prompts 5-endo cyclization to produce 2,5-dihydropyrroles.
Co-reporter:Tomoya Miura ; Takamasa Tanaka ; Kentaro Hiraga ; Scott G. Stewart ;Masahiro Murakami
Journal of the American Chemical Society 2013 Volume 135(Issue 37) pp:13652-13655
Publication Date(Web):August 29, 2013
DOI:10.1021/ja407166r
A stereoselective method for synthesis of trans-2,3-disubstituted 2,3-dihydropyrroles is reported. N-Sulfonyl-1,2,3-triazoles prepared from terminal alkynes generate α-imino rhodium carbene complexes, which when combined with α,β-unsaturated aldehydes produce trans-2,3-disubstituted dihydropyrroles. The method can be successfully applied to a one-pot process starting from terminal alkynes.
Co-reporter:Tomoya Miura ; Yui Nishida ; Masao Morimoto ;Masahiro Murakami
Journal of the American Chemical Society 2013 Volume 135(Issue 31) pp:11497-11500
Publication Date(Web):July 25, 2013
DOI:10.1021/ja405790t
We report a highly diastereo- and enantioselective synthesis of anti homoallylic alcohols from terminal alkynes via (E)-1-alkenylboronates based upon two catalytic reactions: a cationic iridium complex-catalyzed olefin transposition of (E)-1-alkenylboronates and a chiral phosphoric acid-catalyzed allylation reaction of aldehydes.
Co-reporter:Tomoya Miura, Kentaro Hiraga, Tsuneaki Biyajima, Takayuki Nakamuro, and Masahiro Murakami
Organic Letters 2013 Volume 15(Issue 13) pp:3298-3301
Publication Date(Web):June 18, 2013
DOI:10.1021/ol401340u
1-Sulfonyl-1,2,3-triazoles, readily prepared from terminal alkynes and sulfonyl azides, react with allenes in the presence of a nickel(0) catalyst to produce the corresponding isopyrroles. The initially produced isopyrroles are further converted to a wide range of polysubstituted pyrroles through double bond transposition and Alder-ene reactions.
Co-reporter:Dr. Tomoya Miura;Takamasa Tanaka;Tsuneaki Biyajima;Dr. Akira Yada ;Dr. Masahiro Murakami
Angewandte Chemie International Edition 2013 Volume 52( Issue 14) pp:3883-3886
Publication Date(Web):
DOI:10.1002/anie.201209603
Co-reporter:Dr. Tomoya Miura;Takamasa Tanaka;Tsuneaki Biyajima;Dr. Akira Yada ;Dr. Masahiro Murakami
Angewandte Chemie 2013 Volume 125( Issue 14) pp:3975-3978
Publication Date(Web):
DOI:10.1002/ange.201209603
Co-reporter:Tomoya Miura ; Yuuta Funakoshi ; Masao Morimoto ; Tsuneaki Biyajima ;Masahiro Murakami
Journal of the American Chemical Society 2012 Volume 134(Issue 42) pp:17440-17443
Publication Date(Web):October 9, 2012
DOI:10.1021/ja308285r
Enaminones are synthesized by the rhodium(II)-catalyzed denitrogenative rearrangement reaction of 1-(N-sulfonyl-1,2,3-triazol-4-yl)alkanols, which are readily prepared from propargylic alcohols and N-sulfonyl azides. Intramolecular 1,2-hydride (or -alkyl) migration occurs with an intermediary α-imino rhodium(II) carbenoid species generated through denitrogenation of the 1,2,3-triazol-4-yl moiety. The resulting enaminones is converted into various heterocycles with replacement of the N-sulfonyl group.
Co-reporter:Tomoya Miura, Takayuki Nakamuro, Kentaro Hiraga and Masahiro Murakami
Chemical Communications 2014 - vol. 50(Issue 72) pp:NaN10477-10477
Publication Date(Web):2014/07/18
DOI:10.1039/C4CC04786A
A new procedure for the stereoselective synthesis of syn α-amino β-oxy ketones is reported. It consists of two steps; in the first step, α-amino silyl enol ethers having a (Z) geometry are prepared from 1-alkynes via 1-sulfonyl-1,2,3-triazoles. In the second step, the silyl enol ethers undergo the TiCl4-mediated Mukaiyama aldol reaction with aldehydes to produce α-amino β-oxy ketones with excellent syn-selectivity.