An Effective and Environmentally Friendly Synthesis of 1,3-Keto-alcohols
作者:Tülay Yıldız、Hacer Can、Ayşe S. Yusufoğlu
DOI:10.1080/00304948.2019.1693239
日期:2020.1.2
The 1,3-hydroxycarbonyl group is an essential synthon for natural products and bioactive organic molecules. In order to obtain this structure, a number of reaction methods have been developed and, ...
Chemoselective aldol condensation in 5 mol dm−3 lithium perchlorate–nitromethane. A comparison with lithium perchlorate–diethyl ether medium
作者:R. Sudha、S. Sankararaman
DOI:10.1039/a900095j
日期:——
Aldol reactions of silyl enol ethers with aldehydes proceed in 5 mol dm–3 lithium perchlorate–nitromethane medium at ambient temperature. The reaction is highly chemoselective such that only aldehydes and cyclic ketones reacted while acyclic and aromatic ketones failed to react. The same reaction is not promoted in 5 mol dm–3 lithiumperchlorate–diethylether medium. The difference between these two
Asymmetric Aldol Reaction Catalyzed by a Chiral Phosphine-Silver Complex
作者:Akira Yanagisawa、Ryoji Miyake、Kazuhiro Yoshida
DOI:10.1002/ejoc.201402351
日期:2014.7
A catalytic asymmetricaldolreaction of alkenyl trihaloacetates or a γ,δ-unsaturated δ-lactone with aldehydes or an α-ketoester was achieved by using a 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl·silver trifluoromethanesulfonate complex as the chiral precatalyst and N,N-diisopropylethylamine as the base precatalyst in the presence of methanol. Optically active α-alkyl β-hydroxy ketones with enantioselectivities
通过使用 2,2'-双(二苯基膦)-1,1'-联萘·三氟甲磺酸银实现了烯基三卤乙酸酯或 γ,δ-不饱和 δ-内酯与醛或 α-酮酯的催化不对称醛醇反应在甲醇存在下,络合物作为手性预催化剂,N,N-二异丙基乙胺作为碱预催化剂。通过原位生成的手性银烯醇化物,以中等至高产率非对映选择性地获得了对映选择性高达 95% ee 的光学活性 α-烷基 β-羟基酮。
Basic Anion-Exchange Resin-Catalyzed Aldol Condensation of Aromatic Ketones with Aldehydes in Continuous Flow
A general method for the aldol condensation of aromatic ketones with aldehydes was developed under continuous-flow conditions using a commercially available, strongly basic anion-exchange resin (A26) as catalyst. This procedure, in addition to exhibiting a wide substrate scope, promoted carbon–carbon bond formation under mild conditions using a quasi-stoichiometric ratio of starting reagents with good
A catalyticasymmetricaldol reaction of alkenyl trichloroacetates with aldehydes was achieved using dibutyltin dimethoxide and BINAP · silver(I) complex as catalysts in a mixed solvent consisting of THF and MeOH. Various optically active β-hydroxy ketones were diastereoselectively obtained not only from aromatic and α,β-unsaturated aldehydes but also from an aliphatic aldehyde with good enantioselectivity