An efficient synthesis of (E)-4-[7]orthocyclophene (E)-1 via photochemical isomerization of (Z)-1 has been achieved. The key intermediate (Z)-1 was synthesized from commercially available 2-(hydroxymethyl)benzenepropanol (3) in five steps: (i) group-selective Mitsunobu reaction with CH2═CHCH2CH(SO2Ph)2, (ii) oxidation of alcohol, (iii) olefination, (iv) RCM, and (v) removal of sulfones in an overall yield of 73%. The photochemical isomerization of (Z)-1 was efficiently performed in the presence of AgNO3-impregnated silica gel (AgNO3/SiO2). The resulting (E)-1 shows dynamic planar chirality at rt. Enantioenriched (E)-1 was prepared by the HPLC separation of enantiomers using a chiral stationary phase, and the absolute stereochemistry was determined by X-ray diffraction analysis of the Pt-coordinated crystalline derivative. The planar chirality of (E)-1 can be converted into the central chirality of carbon; e.g., the oxidation of (R)-(E)-1 using DMDO provided epoxide (8S,9S)-9 in a stereospecific manner. Furthermore, the Lewis acid-promoted reaction of (8S,9S)-9 afforded a unique tricyclic compound (8S,9S)-10 in an excellent yield and in a stereospecific manner.

The highly enantioselective synthesis of planar-chiral nine-membered cyclic amides was achieved by the Pd-catalyzed asymmetric allylic cyclization of achiral linear precursors in the presence of a catalytic amount of chiral ligand.

A novel nucleophilic substitution reaction at the nitrogen of arylsulfonamides by means of phosphide anions has been described. This reaction allows for the efficient transformation of arylsulfonamides into synthetically valuable phosphamides, amines, and a variety of protected amines.

Pt(0)-catalyzed hydrosilylation of unsymmetric alkynes proceeds in a highly regioselective manner with a dimethylvinylsilyl (DMVS) group as the directing group. This hydrosilylation affords a single regioisomer of silylalkenes from propargylic and homopropargylic alcohol derivatives. DMVS also has an accelerating effect that allows group-selective hydrosilylation of the DMVS-attached alkyne prior to that of other alkynes. Combined hydrosilylation and transformation reactions of the resulting silylalkenes afford various tri-substituted alkenes and multi-oxy-functionalized compounds with high regioselectivity from unsymmetric alkynes.

It has been found that (E)-5-cyclononen-1-one (2a) exhibits marginal planar chirality owing to an insufficient topological constraint, whereas the enolates 3 derived from 2a show robust planar chirality. Enantioenriched enolates are easily prepared by enzymatic hydrolysis, and they show an ability to serve as chiral nucleophiles.

Intermolecular reactions of planar chiral 9-membered diallylic amides provide a variety of bicyclic compounds with central chiralities in a stereospecific fashion with high group selectivity. Lewis-acid-promoted intramolecular reactions of the obtained bicyclic compounds provide transannular products in a stereospecific fashion. Furthermore, a direct transannular reaction of diallylic amide involving sequential intermolecular–intramolecular reactions has been developed.

Enantioselective synthesis of a planar chiral organonitrogen cycle has been newly developed based on the unprecedented prochiral face-selective cyclization of achiral linear precursors by an appropriate chiral promoter.

The planar chiral diolefinic organonitrogen cycles 1 underwent stereospecific and group-selective olefin exchange with 3 to give 4, whose molecular structure was characterized on the basis of NMR and X-ray diffraction. The bonded (E)-olefin moieties in 4 were robust enough to allow untouched (Z)-olefin to undergo epoxidation and hydrogenation to give the corresponding PtCl2(η2-olefin) complexes, whose treatment with PPh3 smoothly liberated their olefinic parts, which would be otherwise difficult to synthesize.