Benzylic Phosphates as Electrophiles in the Palladium-Catalyzed Asymmetric Benzylation of Azlactones
作者:Barry M. Trost、Lara C. Czabaniuk
DOI:10.1021/ja301461p
日期:2012.4.4
Palladium-catalyzedasymmetricbenzylation has been demonstrated with azlactones as prochiral nucleophiles in the presence of chiral bisphosphine ligands. Benzylic electrophiles are utilized under two sets of reaction conditions to construct a new tetrasubstituted stereocenter. Electron density of the phenyl ring dictates the reaction conditions, including the leaving group. The reported methodology
Palladium-Catalyzed Asymmetric Benzylation of Azlactones
作者:Barry M. Trost、Lara C. Czabaniuk
DOI:10.1002/chem.201302390
日期:2013.11.4
Asymmetric benzylation of prochiral azlactone nucleophiles enables the catalytic introduction of a benzyl group towards the synthesis of α,α‐disubstituted amino acids. Herein, we report an enantioselective palladium‐catalyzed process using chiral bis(diphenylphosphinobenzoyl)diamine (dppba) ligands. Naphthalene‐ and heterocycle‐based methyl carbonates react with a number of azlactones derived from
POLYURETHANE RESIN POWDER COMPOSITION FOR SLUSH MOLDING
申请人:SANYO CHEMICAL INDUSTRIES, LTD.
公开号:US20130261240A1
公开(公告)日:2013-10-03
Provided is a polyurethane resin powder composition for slush molding from which an outer skin for an instrument panel can be produced, the outer skin not interfering with deployment of an airbag. More specifically, provided is a polyurethane resin powder composition (D) for slush molding comprising perfectly spherical thermoplastic polyurethane resin particles (A) obtained by reacting a polyester diol component (J) and a diisocyanate component (F), a plasticizer (B), and a vinyl-type copolymer fine particles (C) having a crosslinked structure, wherein the polyester diol component (J) comprises a polyester diol (J1) comprising an aromatic dicarboxylic acid (E) and ethylene glycol as essential constituent units, a ratio of volume average particle sizes of (A) and (C), (A):(C), is 200:1 to 2000:1, and an extent of surface coverage of a surface of (A) with (C) Equation (1)} is 20 to 80%.
[Expression 1]
Extent of surface coverage (%)=[number of particles of (
C
)]×[average cross section area of one particle of (
C
)]/surface area of (
A
)×100 (1)