Selenium stabilized carbanions. .alpha.-Lithio selenoxides as reagents for the synthesis of olefins, allyl alcohols, and dienes
作者:Hans J. Reich、Shrenik K. Shah、Flora Chow
DOI:10.1021/ja00516a026
日期:1979.10
Techniques for the preparation of a-lithio selenoxides have been developed. These reagents react cleanly with most aldehydes and ketones to give 0-hydroxy selenoxides, which can be thermolyzed to allyl alcohols or reduced to hI result of the limited acidifying power of the phenylseleno group, and the propensity of selenides to be fragmented upon treatment with powerful metalating agents. The substantially
已经开发了用于制备α-锂氧化硒的技术。这些试剂可与大多数醛和酮完全反应生成 0-羟基硒氧化物,由于苯基硒基的酸化能力有限,并且硒化物在用强效强效处理后容易碎裂,因此可以将其热解为烯丙醇或还原为 hI。金属化剂。然而,在相应的硒化物酸性不足的情况下,氧化硒预期的显着更高的酸度应该允许它们去质子化。通过与硫化物、亚砜和砜的动力学和热力学酸度数据进行比较,可以推断出硒氧化物相对于硒化物的酸度更高。Bordwell 和同事 5 报告了以下 pK、数据(Me2SO 溶剂和参考文献)。