Degradation of O-arylisoureas in alkali: a low-temperature Chapman-type rearrangement
作者:Nicola A. Suttle、Andrew Williams
DOI:10.1039/p29830001369
日期:——
demonstrated to rearrange intramolecularly to the corresponding NN′-di-isopropyl-N′-arylurea in alkaline solution. The large negative Brønsted-type βL value (–2.3) for the reaction measured against the pK of the corresponding phenol and a modest entropy of activation are consistent with a 1,3-aryl migration. The high efficiency of the migration compared with that of the Chapman rearrangement of O-aryl imidoethers
NN ' -二异丙基- ö -arylisoureas被证明分子内重排以相应的NN ' -二异丙基- ñ “在碱性溶液中-arylurea。在大的负布朗斯台德型β大号值(-2.3)针对该p测得的反应ķ相应的酚和活化的适度熵是与1,3-芳迁移一致的。与O-芳基亚氨基醚的查普曼重排相比,迁移的高效率归因于亚氨基氮的更大的内部亲核性,其在当前情况下带有负电荷。