Quantitative Analyses and Control of Catalytic Organic Transformations

α-(酰氨基)丙烯酸酯与Ru(CH3COO)_2[(S)-BINAP](BINAP=2，2‘-二(二苯基膦)-1，1’-联萘)的不对称氢化反应是通过一氢不饱和机理进行的。用烯胺/金属络合物的立体互补模型解释了与(S)-联苯二胺-Rh相反的对映体选择性。对同分异构体比率的详细分析证明，主要的S对映体和次要的R对映体是通过涉及非对映异构体中间体的相同机理产生的。然而，对于(Z)-3-苯基-2-丁烯酸，次要对映体的形成机理与主要对映体不同。观察到的对映体选择性通常被解释为由单一手性催化剂引起的竞争非对映同形催化循环的结果；然而，这一假设尚未得到证实。我们的研究对这种泛化治疗提出了质疑。此外，在本研究项目中，我们发现了两种新的催化剂：1.Cp^*Rh(III)催化的酮的Leuckart-Wallach(LW)型还原胺化反应；2.[CpRu(CH_3CN)_3]PF_6和2-吡啶甲酸衍生物催化的烯丙基醚的裂解和生成。这两种工艺都非常干净，操作简单。特别是，新的无盐废物的烯丙基醚合成克服了威廉姆森的乙醚合成中长期悬而未决的问题。

Asymmetric hydrogenation of a-(acylamino)acrylic esters with Ru(CH_3COO)_2 [(S)-binap] (BINAP = 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl) has been revealed to proceed via monohydride-unsaturate mechanism. The enantioselectivity that is opposite to the (S)-BINANP-Rh case has been interpreted in terms of stereo-complementary models of the enamide/metal chelate complexes. The detailed analysis of the isotopomer ratios has proved that the major S and minor R enantiomers are produced via the same mechanism involving diastereomeric intermediates. With (Z)-3-phenyl-2-butenoic acid, however, the minor enantiomer is formed mostly by mechanisms that differ from the major one. The observed enantioselectivity has generally been interpreted to result from competing diastereomorphic catalytic cycles caused by a single chiral catalyst; however, this supposition has not been substantiated. Our study calls into question such a generalized treatment. Furthermore, in this research project, we have found two new catalyses 1. Cp^*Rh(III)-catalyzed Leuckart-Wallach (LW)-type reductive amination of ketones and 2. catalytic allyl ether cleavage and formation using [CpRu(CH_3CN)_3]PF_6 and 2-pyridinecarboxylic acid derivatives. Both process are very clean and operational simple. In particular, the new salt waste-free allyl ether synthesis has overcome the long-pending problems in Williamson's ether synthesis.