Selective Magnesiation of Chloro-iodopurines: An Efficient Approach to New Purine Derivatives
作者:Tomáš Tobrman、Dalimil Dvořák
DOI:10.1021/ol053013w
日期:2006.3.1
selective I/Mg exchange reaction with iPrMgCl at -80 degrees C. The reaction course at 0 degrees C is different. Magnesiation of 1 proceeds with the migration of magnesium to the 8 position of the purine nuclei. In the case of 4, substitution of iodine with an alkyl group from the Grignard reagent accompanied with a Cl/Mg exchange reaction takes place, and 6-alkyl-2-magnesiated purines (9) are formed
General Route to Purin-2-ylmagnesium Halides by Metal–Halogen Exchange in Dichloromethane
作者:Silvia Gazzola、Malcolm R. Gordon、Stephen D. Lindell
DOI:10.1055/s-0039-1690818
日期:2020.3
solution of a 9-alkyl- or 9-aryl-2-iodopurine in dichloromethane with an ethereal solution of ethylmagnesiumbromide at –5 °C generates the corresponding purin-2-ylmagnesium bromide, which reacts with aldehydes to give the corresponding 2-(hydroxyalkyl)purines in yields of 53–84%. The purin-2-yl Grignardreagents show good functional-group tolerance to ester and nitro groups, and the method permits the