A new and more powerfully activating diamine for practical and scalable enantioselective aldehyde crotylsilylation reactions
作者:Linda M. Suen、Michael L. Steigerwald、James L. Leighton
DOI:10.1039/c3sc50714a
日期:——
A new diaminophenol ligand for crotylsilylation reactions with cis- and trans-crotyltrichlorosilane has been developed. The conformational constraints that result from the tethering of the phenol to one of the amino groups attenuate the stereoelectronic effects that reduce activity in the corresponding untethered diaminosilanes, and the resulting crotylsilane reagents are as active as our previously
一种新的二氨基苯酚配体,用于与顺式和反式巴豆基三氯硅烷已经被开发出来。苯酚与氨基之一的束缚导致的构象限制减弱了降低相应未束缚二氨基硅烷活性的立体电子效应,由此产生的巴豆基硅烷试剂与我们之前报道的 EZ-CrotylMix 试剂一样具有活性,但不需要Sc(OTf) 3催化剂的使用。反过来,这使得开发出一种实验上简单、可持续、高效和可扩展的一锅法程序,可以在≤8 小时内进行,其中二氨基苯酚活化剂配体可以很容易地以≥90% 的收率通过以下方式回收:重结晶。