The chemistry of phosphorodiselenoates: structure, catalysis and formation of Se-esters
作者:Bijay Sarkar、Chiang-Shiang Fang、Lee-Yan You、Ju-Chun Wang、C. W. Liu
DOI:10.1039/b813267d
日期:——
Though metal complexes of dialkyl diselenophosphate ligands [Se2P(OR)2]− (dsep) have been reported in several occasions, the solid-state structure of isolated dsep ligands is still unknown. Herein the ammonium salt of the dsep ligand, NH4Se2P(OiPr)2, is structurally characterized and N–H⋯Se type of H-bonding interactions are revealed. In addition, the NH4Se2P(OR)2 ligands serve as an ammonia source in the Fe powder catalyzed condensation of acetone with ammonia to form 2,2,6,6-tetramethyl-4-oxopiperidinium salts of the dsep ligand, [H2N(CH2)2(CMe2)2CO}Se2P(OR)2}] (1a = iPr, 1b = Et) of which 1b is structurally characterized. Novel syntheses of Se-esters of O,O′-dialkylphosporodiselenoic acid, 2, 3, 4, 5, 6, 7, directly from the ammonium salts have been achieved. The reactions, where one of the Se atoms of the dsep unit acts as the nucleophilic center, include Michael addition, epoxide ring opening addition, acylation and α-alkynation.
虽然二烷基二硒磷酸盐配体 [Se2P(OR)2]- (dsep)的金属配合物已被多次报道,但分离出的 dsep 配体的固态结构仍然未知。本文对 dsep 配体的铵盐 NH4Se2P(OiPr)2 进行了结构表征,并揭示了 N-H⋯Se 类型的 H 键相互作用。此外,在铁粉催化丙酮与氨的缩合过程中,NH4Se2P(OR)2 配体可作为氨源,生成 dsep 配体的 2,2,6,6-四甲基-4-氧代哌啶鎓盐 [H2N(CH2)2(CMe2)2CO}Se2P(OR)2}] (1a = iPr,1b = Et),其中 1b 具有结构特征。从铵盐直接合成 O,O′-二烷基磷酰二硒酸的 Se 酯 2、3、4、5、6、7 的新方法已经实现。这些反应包括迈克尔加成、环氧化物开环加成、酰化和 α-炔化反应。