The first catalytic dehydrative condensation of the benzylic C-H bonds of toluene and p-xylene with aromatic aldehydes is reported herein. This protocol provides highly atom-economical access to stilbene and p-distyrylbenzene derivatives, whereby water is the sole byproduct. The reaction is based on the deprotonation-functionalization of benzylic C-H bonds through η6-complexation of the arenes, which
本文报道了甲苯和对二甲苯的苄基 CH 键与芳香醛的第一次催化脱水缩合。该协议提供了对二苯乙烯和对二苯乙烯基苯衍生物的高度原子经济访问,其中水是唯一的副产品。该反应基于通过芳烃的 η6-络合实现苄基 CH 键的去质子化功能化,这是首次使用催化量的过渡金属活化剂实现的。该方法成功的关键是使用磺酰胺阴离子作为催化剂组分,这似乎不仅有助于苄基 CH 键的去质子化,而且还有助于通过亲电子甲苯磺酸亚胺中间体形成 CC 键。
A Convenient One-Pot Synthesis of Bis[(<i>E</i>)-4-halostyryl]arene Derivatives
A newconvenient synthetic protocol for the one-pot ste- reoselective synthesis of bis((E)-4-bromo(or chloro)styryl)arene derivatives via the sequential reaction of silylative-coupling of 4- halostyrenes with vinylsilanes followed by palladium-catalyzed cross-coupling 4-halostyrylsilanes with diiodoarenes, is described. The reaction leads to symmetrical bis((E)-4-halostyryl)arene deriv- atives obtained