Copper-catalysed heteroannulation with alkynes: a general and highly regio- and stereoselective method for the synthesis of (E)-2-(2-arylvinyl) quinazolinones
作者:Nitya G Kundu、Gopeswar Chaudhuri
DOI:10.1016/s0040-4020(01)00637-8
日期:2001.7
A highly regio- and stereoselective procedure for the synthesis of 2-substituted-1,2,3,4-tetrahydroquinazolinones through a two-step procedure, e.g. (i) palladium–copper catalysed C-arylation of terminal alkynes and (ii) copper-catalysed cyclisation of disubstituted alkynes, is described. 2-(N-Alkyl-N-prop-2′-ynyl)amino-N′- p-tolyl benzamides 5a and 5b reacted with aryl iodides 2 in the presence of
通过两个步骤合成2-取代的1,2,3,4-四氢喹唑啉酮的高度区域选择性和立体选择性的方法,例如(i)钯-铜催化的末端炔烃的C-芳基化和(ii)铜描述了双取代炔烃的-催化的环化。2-(Ñ -烷基- ñ -丙-2'-炔基)氨基- ñ ' - p -甲苯基苯甲酰胺5A和5B与芳基碘化物反应2中(PH的存在3 P)2的PdCl 2(2.5摩尔%) ,CuI(5 mol%),Et 3 N(5当量)的CH 3CN在室温16小时,得到二取代的炔烃6 - 18,其然后可以用的CuI(20摩尔%)环化,K 2 CO 3(2.5当量),卜4 NBR(1个当量)在CH 3 CN在80°C持续16-24 h,得到1-甲基(苄基)-(E)-2-(2-芳基乙烯基)-3-对甲苯基-1,2,3,4-四氢喹唑啉-4-酮19 –丰产31。只在少数情况下,苯并二氮杂酮32 - 34可以以低产率获得。还描述了新型尿嘧啶衍生物35和36的合成。