Zur Regioselektivit�t der Umsetzung von Methallylisothiocyanat mit monosubstituierten Hydrazinen
摘要:
Methallyl isothiocyanate 1 reacts with substituted aryl hydrazines to 1,4- respectively 2,4-disubstituted thiosemicarbazides 4 and 5 in dependence on the reaction conditions and the nature of the aryl group. The influence of the substituents is discussed. The novel N'-mono- and disubstituted N-methallylic thioureas 2 and 3 are synthesized.
A simple and efficient method has been developed for the synthesis of N-allylthioureas from allylic bromides in one-pot by using a supported reagents system, KSCN/SiO2–RNH3OAc/Al2O3, in which allyl bromide reacts first with KSCN/SiO2 and the product, allyl isothiocyanate, reacts with RNH3OAc/Al2O3 to give the final product, N-allylthiourea, in good yield.
通过使用支持的试剂系统KSCN / SiO 2 -RNH 3 OAc / Al 2 O 3,由一锅法从烯丙基溴中合成N-烯丙基硫脲的简单有效方法已被开发,其中烯丙基溴首先与KSCN / SiO 2和产物异硫氰酸烯丙酯与RNH 3 OAc / Al 2 O 3反应,以高收率得到最终产物N-烯丙基硫脲。