The preparative aspects of the addition of nucleophiles to alkyne-derivatives having both push- and pull-groups (1) are discussed: The addition of primary and secondary amines as well of aliphatic alcohols to the alkyne-derivatives 1 in most cases predominantly yields the Michael-adducts 2–10. The importance of a side-reaction consisting in an addition of amines to C(2) of the alkyne-derivatives 1
Die Addition von Säuren an Alkinderivate mit Push-pull-Gruppen,
作者:Andreas Niederhauser、Markus Neuenschwander
DOI:10.1002/hlca.19730560416
日期:1973.4.25
The addition of proton acids as HF, HCl, HBr, HOAc and phenol to alkyne-derivatives of the type (CH3)2NCCCOR(1) yielding the adducts 2 to 6 is investigated. The stereochemical course of the reaction is mainly influenced by the structure of the alkyne 1. Kinetic investigations show that the rate of the third-order-reaction increases from 1 a (RH) to 1 b (R CH3) and 1 c (R OCH3) and decreases drastically
研究了质子酸如HF,HCl,HBr,HOAc和苯酚向(CH 3)2 NCCCOR(1)型炔烃衍生物的加成反应,生成加合物2至6。反应的立体化学过程主要受炔烃1的结构影响。动力学研究表明,在极性溶剂中,三级反应的速率从1a(RH)增至1b(R CH 3)和1c(R OCH 3),并显着降低。根据这些结果,概述并讨论了反应机理。
Push-pull-Cyclobutadiene
作者:M. Neuenschwander、A. Niederhauser
DOI:10.1002/hlca.19700530308
日期:——
Two push-pull-cyclobutadienes 10b and 10c are prepared by reaction of two eq. of the corresponding acetylenes having electrondonating and electronaccepting groups (4) with one eq. of HBF4 to cyclic cyanine salts, followed by elimination of HBF4 with KOC(CH3)3. These cyclobutadienes, stable in cristalline form at room temperature respectively for a short time (10b RCH3) or for several days (10c ROCH3)