| The ylides derived from transition-metal carbenoids with aldehydes, ketones and imines can undergo 1,3-dipolar cycloaddition reaction with a range of dipolarophiles, or cyclization by themselves. Among the ylide reactions, 1,3-dipolar cycloaddition reaction is the most general reaction and there have been few examples of cyclication. The cyclications of ylide to three-membered ring (epoxide and aziridine formation) have received a great deal of attention. For the first time, we fulfilled the chemospecific and stereospecific epoxidation of diazophosphonate with aldehydes and ketone in the presence of dirhodium complexes catalyst. The high stability of carbonyl ylide generated from the carbenoid is favorable to its cyclization giving the cis-epoxide compounds in good yield, and 1,3-dipolar cycloaddition reaction as a competitive process had not been observed. The different catalysts, catalyst loading, reaction temperature, solvent and amount of aldehyde have no effect on the chemoselectivity and stereoselectivity of the epoxidation. Our studies developed a novel method for synthesis of these oxirane-2-phosphonates. Furthermore, this thesis reported the highly stereoselective synthesis of trans-aziridine through Rh2(OAc)4 catalyzed aziridination of dimethyl diazophosphonate with arylimines. The stereochemistry of products was characterized based on the single crystal X-ray analysis. The reaction pathway involves ylide intermediate in situ generated from diazocompound with an arylimine, which undergoes intramolecular ring closure to give aziridine-2-phosphonate. In addition, several reaction systems of multi-component containing dimethyl diazobenzylphosphonate were explored, but the novel three-component reaction was unable to be performed in conditions used before. The experiments provided some evidences for the mechanisms of aldehyde epoxidation, N-H insertion and O-H insertion and benefited to us intensive understanding the reactivity of diazobenzylphosphonate.
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