Scope and Limitations of the Nitro-Mannich Reaction for the Stereoselective Synthesis of 1,2-Diamines
作者:James C. Anderson、Alexander J. Blake、Gareth P. Howell、Claire Wilson
DOI:10.1021/jo048304h
日期:2005.1.1
p-methoxybenzyl (PMB) or p-methoxyphenyl (PMP) in the Lewis acid-catalyzed addition reactions. Reduction with SmI2, treatment with COCl2, followed by OMB deprotection gave diastereomerically pure cis-imidazolidinones in 55−79% overall yield from imine. Preliminary results have shown that acetic acid can catalyze the reaction of N-OMB-benzylideneamine with nitropropane, used as solvent, to give the thermodynamically
乙酸促进的硝基丙酸锂的加成反应和路易斯酸催化的[Sc(OTf)3,Cu(OTf)2或Ti(O i Pr)4)的加成反应生成三甲基甲硅烷基硝基丙酸酯到一系列杂芳族和简单的脂肪族醛亚胺中以> 95%的收率得到抗富集的(〜3-19:1)β-硝胺,为动力学产物。发现在路易斯酸催化的加成中,非极性N-亚胺保护基对于与邻甲氧基苄基(OMB)的反应性至关重要,与对甲氧基苄基(PMB)或对甲氧基苯基(PMP)相比,具有更好的选择性和更高的收率。反应。减少SmI 2,用COCl 2处理,再用OMB脱保护,得到非对映体纯的顺式-咪唑啉酮,其亚胺的总产率为55-79%。初步结果表明,乙酸可以催化N -OMB-亚苄基胺与用作溶剂的硝基丙烷的反应,从而提供热力学上更稳定的顺式-β-硝基胺产物。