Chiral monodentate phosphine ligands for the enantioselective α- and γ-arylation of aldehydes
作者:Ivan Franzoni、Laure Guénée、Clément Mazet
DOI:10.1016/j.tet.2014.02.079
日期:2014.7
phosphine ligands elaborated on the binepine scaffold is described. Their application in the Pd-catalyzedintramolecularasymmetricα-arylation of aldehydes and the intermolecular asymmetric γ-arylation of α,β-unsaturated aldehydes provides a mean of validating the design of these ligands. For the first reaction, excellent reactivities have been obtained while only modest enantioselectivities were measured
[EN] SUBSTITUTED BUTANOL DERIVATIVES AND THEIR USE AS FRAGRANCE AND FLAVOR MATERIALS<br/>[FR] DÉRIVÉS SUBSTITUÉS DU BUTANOL, ET LEUR UTILISATION EN TANT QUE PARFUMS ET ARÔMES
申请人:TAKASAGO PERFUMERY CO LTD
公开号:WO2010002386A1
公开(公告)日:2010-01-07
The present invention is related to substituted butanol derivatives of the formula; wherein R is an unsubstituted or substituted C1-6 straight chain alkyl, an unsubstituted or substituted C3-6 branched chain alkyl an uosubstituted or substituted C3-6 straight chain alkenyl, an unsubstituted or substituted Cu= branched chain alkenyl, an unsubstituted or substituted C3-6 cycioalkyl, an unsubstituted or substituted C1-6 alkoxy, nitiile, halo, amino, an unsubstituted or substituted C1-6 alkyiamino, w. unsubstituted or substituted C1-6 dialkyfaraino, carboxy-C1-6 alkyiamino, carboxy-C1-6 di alkyl amino, an unsubstituted or substituted acetoxy, carboxy, an unsubstituted or substituted carboxyethyi, an unsubstituted or substituted C1-6 aikylcarbonyi, an unsubstituted or substituted C1-6 aikylcarboxy, ao unsubsiituted or substituted C1-6 alkylthio, an unsubstituted or substituted C1-6 alkyloxy. carboxamido, an unsubstituted or substituted C1-6 alkylcarboxarøido or an unsubstituted or substituted C1-6 dia'lkylcarboxamido. Such compounds are useful in flavor or flavor compositions.
Chiral Counteranions in Asymmetric Transition-Metal Catalysis: Highly Enantioselective Pd/Brønsted Acid-Catalyzed Direct α-Allylation of Aldehydes
作者:Santanu Mukherjee、Benjamin List
DOI:10.1021/ja074678r
日期:2007.9.1
Pd/chiral acid-catalyzed α-allylation of α-branched aldehydes with an allyl amine as the allylating species that creates all-carbonquaternary stereogenic centers in high yields and enantioselectivities. To our knowledge, this is the first time that a chiral anionic ligand is applied for achieving asymmetric induction in a palladium-catalyzedallylicalkylation reaction.
The Proline-Catalyzed Asymmetric Amination of Branched Aldehydes
作者:Thomas Baumann、Henning Vogt、Stefan Bräse
DOI:10.1002/ejoc.200600654
日期:2007.1
An efficient access to configurationally stable α,α-disubstituted α-amino aldehydes, oxazolidinones, and α-amino acids has been presented. Starting from simple and easily available racemic aldehydes, the α-aminated products were obtained using azodicarboxylates as the nitrogen source in up to 86 % ee and moderate to excellent yield. These products could further be converted both into the corresponding
Diastereofacial selectivity via aldol reactions using ethyl dithioacetate and ethyl dithiopropionate enolates
作者:A.I. Meyers、Robert D. Walkup
DOI:10.1016/s0040-4020(01)96754-7
日期:1985.1
The lithium enolate of ethyldithioacetate reacts with α-methyl aldehydes to yield the aldol products in which the syn configuration in the positions β and γ to the thiocarbonyl of the product is favored over the anti configuration. This selectivity is solvent-dependent, and is enhanced at lower temperatures. In most cases, syn:anti product ratios obtained under these conditions varied from 57:43 to