Yuichiro Kondo

Bowl‐Shaped Tris(2,6‐diphenylbenzyl)tin Hydride: A Unique Reducing Agent for Radical and Ionic Chemistry

Unique selectivity, hitherto not observable in ordinary radical and ionic reactions, is achieved with the bowl-shaped tris(2,6-diphenylbenzyl)tin hydride (TDTH; see structure), which has been successfully utilized as a new reducing agent.

Unprecedented Encapsulation of Carbonyl Guest with Designer Lewis Acid Receptor

A reaction chamber is formed by a cage compound in which a dicarbonyl guest molecule is encapsulated by two bowl-shaped aluminum tris(2,6-diphenylphenoxide) molecules through Lewis acid-base interactions (structure of complex with 1,4-dimethylpiperazine-2,5-dione depicted). The carbonyl compound held inside the molecular capsule is effectively protected against the approach of external nucleophiles. On the other hand, the chamber is large enough to allow Diels-Alder cycloadditions to take place under mild conditions and with high selectivity.

Conjugate allylation to α,β-unsaturated aldehydes with amphiphilic alkylation system, ATPH/allylcerium reagents

Abstract Conjugate allylation to α,β-unsaturated aldehydes has been successfully accomplished with a new amphiphilic alkylation system, aluminum tris(2,6-diphenylphenoxide) (ATPH)/allylcerium reagents. Diallycerium chloride was found to be the most satisfactory among several allylcerium reagents.

Tris(2,6-diphenylbenzyl)amine (TDA) and tris(2,6-diphenylbenzyl)phosphine (TDP) with unique bowl-shaped structures: synthetic application of functionalized TDA to chemoselective silylation of benzylic alcohols

Abstract A new strategy for obtaining the formal steric hindrance of tertiary amines by remote steric factors is described by designing the bowl-shaped, structurally unique tris(2,6-diphenylbenzyl)amine (TDA). In addition to its structural uniqueness, TDA possesses the rich electronic atmosphere derived from three 2,6-diphenylbenzyl moieties, thereby allowing the chemoselective silylation of benzylic alcohols preferentially over other alcohols based on the effective aromatic π,π interaction. This approach of preparing TDA is also applicable to the new synthesis of tris(2,6-diphenylbenzyl)phosphine (TDP).

Evaluation of several fluorinated ATPH derivatives as functionalized Lewis acid receptors for conjugate alkylation to α,β-unsaturated aldehydes with alkyllithium nucleophiles

Abstract Several fluorinated aluminum tris(2,6-diphenylphenoxide) (ATPH) derivatives have been synthesized to evaluate, as functionalized Lewis acid receptors, the conjugate alkylation ability to α,β-unsaturated aldehydes by the combined use of alkyllithium nucleophiles. Among these, 3,4,5-F 3 -ATPH was found to be the most satisfactory.