The invention relates to a process for the preparation of vinyl pyrimidines of the formula I
wherein R1 is hydrogen or a carboxylic ester group, and R2 is hydrogen or a group of the formula (a)
wherein Ra is hydrogen, a protecting group or a group easily hydrolyzable under physiological conditions,
by reacting a compound of the formula II
wherein R21 is hydrogen or a group (a) wherein hydroxy groups are optionally protected, R3 is bromo, chloro or iodo, and R1 is as above, with a vinyl borane compound in the presence of a Pd complex and a base, and optionally, further reacting a product of formula I wherein R2 is hydrogen with a compound of the formula IV
wherein Rb is a hydroxy protecting group and Z is a leaving group, in the presence of a Lewis acid catalyst.
本发明涉及一种制备式 I
乙烯基嘧啶的工艺
其中 R1 是氢或
羧酸酯基团,R2 是氢或式(a)的基团
其中 Ra 是氢、保护基团或在生理条件下易
水解的基团、
使式 II 的化合物反应
其中 R21 是氢或基团 (a),其中羟基可选择被保护,R3 是
溴、
氯或
碘,R1 如上,在
钯络合物和碱存在下与
乙烯基硼烷化合物反应,并可选择将式 I 的产物(其中 R2 是氢)与式 IV 的化合物进一步反应
其中 Rb 为羟基保护基团,Z 为离去基团,在
路易斯酸催化剂存在下进一步反应。