Studies On The Michael Addition-condensation Tandem Reaction Of Aminothiophenol To α,β-unsaturated Ketones Catalyzed By CeCl₃·7H₂O-NaI

CeCl3·7H2O as one of the most significant catalyst in Michael addition has beenexplored extensively for the conformation of carbon-carbon bond, carbon-oxygen bond andcarbon-nitrogen bond. However, few research results have been reported the effectivecatalytic performance of CeCl3·7H2O in the S-Michael addition and the condensationreaction of the amino group with carbonyl group.Our research group have been engaged in the synthesis of1,5-benzothiazepine byeffective Michael addition from amino ketones for many years. We found that catalysts whichwere commonly employed in Michael addition can not promote the reaction effectivelybecause of the large steric hindrance of the substrate except CeCl3·7H2O-NaI. Stimulated bythese results, in this dissertation, we present a series of research focused on CeCl3·7H2O-NaIcatalyzed the Michael addition reaction of aminothiophenol with high resistanceα,β-unsaturated ketone. And the universality and repeatability of this catalyst were alsoexplored in detail.1、 The optimal reaction condition of Michael additionFirstly, series of detailed research and analysis of catalyst, solvent and other aspectsthrough a model Michael addition reaction has been carried out. Ultimately we optimized thebest reaction condition of CeCl3·7H2O-NaI catalysted Michael addition reaction of theaminothiophenol with α,β-unsaturated ketone5c.2、 The universality of the CeCl3·7H2O-NaI as catalystSecondly, the Michael addition reaction of aminothiophenol adopted differntα,β-unsaturated ketones with large sterically hindered have been carried out to explain theuniversality of catalytic effect of CeCl3·7H2O-NaI. And all result revealed the excellentcatalytic performance in Michael addition reaction with desired yield and relatively shortreaction time.3、 The repeatability of the CeCl3·7H2O-NaI as catalystThirdly, the study found that the catalyst also can keep some catalytic effect and havegood value when used for four times.4、 Synthesis of intermediate substratesFinally, With bromobenzene and anhydride as raw materials,14differnt α,β-unsaturatedketones (5a~5n) with large sterically hindered have been synthesised by friedel-crafts acyl reaction, esterification and aldol condensation reaction.