Studies On [4+2] Annulations Of α-Alkylallenoates With Arylidenemalononitriles Catalyzed By Triphenylphosphine

This thesis is composed of three parts:(1) Nucleophilic phosphine and amine catalysis has proven to be a powerful tool in organic synthesis. Investigations in this area have established a range of suitable coupling partners for allenoates, including electron-deficient olefins, imines, and aldehydes. Especially, Nucleophilic phosphine catalysis which can provide easy access to cyclic, bicyclic or polycyclic carbocycles and heterocycles. This chapter will summary the recent achievements in this area.(2) We have developed a [4+2] annulations of a-alkylallenoates with arylidenemalononitriles catalyzed by triphenylphosphine. The highly functionalized cyclohexene derivatives were afforded in moderate yields (60-78%).(3) We have developed the asymmetric addition reactions of nucleophilic acetylides to a-amino N-tert-butanesulfinimines, which were synthesized from L-amino acids. The desired a-(phthaloyl-imide) propargyl amines were obtained in good distereoselectivities (95:5 to>99:1 dr) under optimized conditions. The propargyl diamine was obtained by deprotecting of the phthalimide and N-tert-butanesulfinyl groups.