Switchable Palladium-Catalyst Reaction of Bromomethyl Sulfoxides, CO, and N-Nucleophiles: Aminocarbonylation at Csp<sup>3</sup> versus Oxidative Carbonylation of Amines
作者:Cristian Mollar、Carmen Ramirez de Arellano、Mercedes Medio-Simón、Gregorio Asensio
DOI:10.1021/jo301778n
日期:2012.11.2
primary or secondary amines. The reaction with ambident nucleophiles such as amino alcohols was highly selective and took place exclusively at the amino group despite the presence of the alcohol functionality. In parallel to the reaction paths for simple amines, amino alcohols were converted into hydroxy sulfinyl amides when the reaction was catalyzed by Pd-xantphos, while Pd(PPh3)4 catalyst afforded cyclic
根据催化体系和反应条件,α-溴甲基亚砜,一氧化碳和N-亲核试剂的钯催化反应遵循不同的反应路径。Pd-黄原磷催化剂通过氨基羰基化过程提供高产率的α-亚磺酰基酰胺,并且是非苄基sp 3-杂化碳的这种类型转化的第一个实例。另一方面,胺的氧化羰基化与α-溴甲基亚砜,一氧化碳和催化性Pd(PPh 3)4一起发生。在有氧条件下,由伯胺或仲胺生成脲和草酰胺。与环境亲核试剂(如氨基醇)的反应具有高度选择性,尽管存在醇官能团,但仅在氨基上进行。与简单胺的反应路径平行,当Pd-xantphos催化反应时,氨基醇转化为羟基亚磺酰基酰胺,而Pd(PPh 3)4催化剂提供了环状氨基甲酸酯。还描述了溴甲基亚砜与简单的醇和CO的烷氧基羰基化反应,生成相应的亚磺酰基酯。