Liquid-liquid phase transfer alkylation of 4-methoxy-pyrazolo[3,4-d]-pyrimidine (1a) with a dichloromethane/dibromomethane mixture (3:1, v/v) gave the regioisomeric methylenebis(heterocycles) 3a–5a. These were converted by dilute aqueous sodium hydroxide containing dimethylsulfoxide (DMSO) at concentrations between 0 and 60 vol-% into the methylenebis(allopurinols) 3b–5b by nucleophilic SNAr reactions at C(4). The effect of DMSO on the reaction kinetics was investigated.
用
二氯甲烷/
二溴甲烷混合物(3:1,v/v)对 4-甲氧基
吡唑并[3,4-d]-
嘧啶(1a)进行液-液相转移烷基化反应,可得到亚甲基双(杂环)3a-5a。这些物质在含有
二甲基亚砜(
DMSO)的稀
氢氧化钠水溶液(浓度介于 0 和 60 vol-% 之间)中,通过亲核 SNAr 反应在 C(4)处转化为亚甲基双(异
嘌呤醇)3b-5b。研究了
DMSO 对反应动力学的影响。