Additions of carbenium ions to nonconjugated dienes. The retarding (−I)-effect of the second double bond.
作者:Bernhard Irrgang、Herbert Mayr
DOI:10.1016/s0040-4020(01)80918-2
日期:1991.1
Kinetics for the addition of the p-methoxybenzhydryl cation (AnPhCH+, 10) towards nonconjugated dienes 11 [H2C=C(CH3)-(CH2)n-C(CH3)=CH2] have been determined in CH2Cl2 at −30° to −70°C. Reactivity increases with increasing number of methylene groups separating the two double bonds. For n = 4, reactivity reaches the value for saturated alkyl substituents, and nucleophilic assistance of the second double
已经确定了在非共轭二烯11 [H 2 C = C(CH 3)-(CH 2)n -C(CH 3)= CH 2 ]上将对甲氧基苯甲酰基阳离子(AnPhCH +,10)加成的动力学。在30°至-70°C下的CH 2 Cl 2。反应性随着分离两个双键的亚甲基数目的增加而增加。对于n = 4,反应性达到饱和烷基取代基的值,并且从未观察到第二个双键的亲核助剂。