Ikuya Shibata

Solvent-controlled addition of alkynyltins or allylic tins to aldehydes catalyzed by indium trichloride

Abstract Indium trichloride promoted catalytically the addition of alkynyltins or allylic tins to aldehydes in two ways: transmetallation with the tin compounds and activation of aldehydes as a Lewis acid. The stcreochcmical outcome in the addition of cinnamyltributyltin to an aldehyde strongly indicates that control of the process can be achieved simply by the choice of solvent acctonitrile or dichloromethane.

Preparation of a novel indium hydride and application to practical organic synthesis

Abstract Dichloroindium hydride was first generated using the transmetalation between indium trichloride and tributylstannane at −78 °C, and the generation was confirmed by IR and NMR measurements. The resulting hydride is considerably stable even at ambient temperature due to the coordination of THF, such that it is applicable to practical reduction of carbonyls and halides.

Indium hydride: a novel radical initiator in the reduction of organic halides with tributyltin hydride

Abstract Dichloroindium hydride (Cl2InH), which was generated in situ by transmetallation between tributyltin hydride and indium trichloride, acted as a novel radical initiator for the reduction of organic halides with tributyltin hydride. The reaction was revealed to proceed through a radical process under non-oxygen conditions at room temperature, and to be applicable to intramolecular radical cyclizations.

Regioselective ring cleavage of oxiranes catalyzed by organotin halide - triphenylphosphine complex

Abstract Vicinal chloroesters are formed in high yield from the reaction of oxiranes and benzoyl chloride in the presence of organotin halide - triphenylphosphine complex with enhanced regioselectivity in oxirane ring cleavage.

Selective reduction of acid chloride with a catalytic amount of an indium compound

Abstract Indium hydride generated from tributyltin hydride and indium trichloride was coordinated by a phosphine to reduce acid chlorides to the corresponding aldehydes selectively. This reaction was achieved by a catalytic amount of indium trichloride.

Bu2SnIH-promoted proximal bond cleavage of methylenecyclopropanes and successive radical cyclization and/or Pd-catalyzed coupling reaction.

The unprecedented regioselective hydrostannation of methylenecyclopropanes to give vinyltins was achieved using dibutyliodotin hydride (Bu2SnIH), which could be applied to intramolecular radical cyclization.

Remarkable Dependence of Diastereoselectivity on Anhydrous or Aqueous Solvent in the Indium Hydride Promoted Reductive Aldol Reaction of α,β‐Unsaturated Ketones

Dichloroindium hydride generated by the transmetallation between tributyltin hydride and indium trichloride predominantly reduced α,β-unsaturated ketones (enones) with 1,4-selectively even in the presence of aldehydes. Under anhydrous conditions, the successive aldol reaction between the resulting enolates and the remaining aldehydes proceeded with high anti-selectivity. The stereochemistry was dramatically reversed to be syn-selective by the use of water and methanol as an additive and solvent, respectively.

Allylic tin(IV)-tin(II) chloride-acetonitrile as a novel system for allylation of carbonyls or imines

Abstract Effective allylation of aldehydes, ketones and imines was accomplished by allylic tributyltins 1 in the presence of SnCl 2 in an acetonitrile solution. In this reaction system. Sn(IV) Sn(II) transmetallation must play a key role, generating the allylic tin(II) reagents as a novel reacting species. Acetonitrile effectively promoted the transmetallation to give anti -adducts in the reaction with cinnamyltin 1c , whereas dichloromethane disturbed the transmetallation to produce syn -adducts.

A Highly syn-Selective Allylation of Aldehydes in Water

nBu4NBr/PbI2 acts as an effective catalyst for the allylation of aldehydes 2 with the allylic tin reagents 1 in water. A high syn-selectivity of 3 was achieved in water without any aprotic solvents in the reaction of the aromatic aldehydes 2 with the crotyltri-n-butyltin reagents 1b, 1c irrespective of their E/Z geometry.

Synthesis of carbocycles by enone-selective reduction using organoiodotin hydride

Abstract By using di- n -butyliodotin hydride ( n -Bu 2 SnIH), carbocycles were prepared from substrates bearing both enone and formyl moieties, where the enone-selective reduction was followed by a diastereoselective intramolecular aldol reaction.