Exploiting Coordination Effects for the Regioselective Zincation of Diazines Using TMPZnX⋅LiX (X=Cl, Br)
作者:Alexander Kremsmair、Alisa S. Sunagatullina、Leonie J. Bole、Pasquale Mastropierro、Simon Graßl、Henrik R. Wilke、Edouard Godineau、Eva Hevia、Paul Knochel
DOI:10.1002/anie.202210491
日期:2022.10.4
N-heterocycles such as pyrimidines were regioselectively zincated using bimetallic bases of type TMPZnX⋅LiX (TMP=2,2,6,6-tetramethylpiperidyl; X=Cl, Br) and subsequently quenched with electrophiles. Trapping of key organometallic intermediates has shed light on their complex solution constitution and helped to explain the high regioselectivity observed as well as the stoichiometry of the base used.
使用 TMPZnX·LiX 型双金属碱(TMP=2,2,6,6-四甲基哌啶基;X=Cl,Br)对重要的N杂环(例如嘧啶)进行区域选择性锌化,然后用亲电子试剂淬灭。关键有机金属中间体的捕获揭示了它们复杂的溶液组成,并有助于解释观察到的高区域选择性以及所用碱的化学计量。