Synthesis of enantiopure C3-symmetric bulky trialkanolamines and their enantioselective inductivity during the alkynylation of aldehydes
摘要:
Several C-3-symmetric trialkanolamines can be efficiently obtained via molecular sieve-assisted epoxide ring opening with ammonia in high yields (up to 90%) and regioselectivity up to 100%. These trialkanolamines were effective for the asymmetric alkynylation of aldehydes and the propargyl alcohols were obtained in high yields (up to 92%) and high enantiomeric excesses (up to 95%). The H-1 NMR spectra support that there could be a complex mixture of polynuclear Ti(IV)-based species form from the interaction of Ti(IV) with ligand. (C) 2014 Elsevier B.V. All rights reserved.
通过使9-烷基芴-9-基锂与光学活性环氧氯丙烷在-70°C下反应,合成一系列光学活性3-(9-烷基氟-9-基)丙烯氧化物,并使用KOH作为引发剂进行聚合。聚(3-(9-烷基氟-9-基)环氧丙烷)的分子量大于聚(4,4,4-三苯基-1-丁烯氧化)的分子量,已证明具有稳定的分子量。溶液中呈螺旋状构象,分子量分布较窄(M w / M n 比聚(4,4,4-三苯基-1-丁烯氧化物)= 1.02至1.09)。通过研究衍生自光学活性环氧化物的一系列聚合物的手性,表明聚(3-(9-烷基氟-9-基)丙烯氧化物)在溶液中保持单手螺旋构象。