Intramolecular reactions epoxide cleavage

Table 5.7. We have attempted to activate the epoxide using Lewis acids to accelerate the organometallic epoxide-opening reaction, but to no avail. Analogously, intramolecular cyclizations via an epoxide cleavage process can also be realized. For example, treatment of 6-bromo-l,2-epoxyhexane with thienyl-based copper resulted in intramolecular cyclization subsequent...

The optically active N-aminoindoline (265) has been applied to the asymmetric synthesis of a variety of a-amino acids (70JA2476, 2488). Starting from TV-benzoyl-1,2,3,4-tetrahy-droquinaldine (257), the chloro amide (258) was prepared by von Braun cleavage. Thermolysis converted (258) to the rrans-unsaturated amide (259) which was epoxidized. On base treatment the epoxide (260) underwent intramolecular nucleophilic displacement and amide hydrolysis to afford indoline (261) stereospecifically. Resolution of (261) was accomplished via the brucine salt of the N-o-carboxybenzoyl derivative (262). Alkaline hydrolysis, N-nitrosation and reduction yielded the levorotatory 1-aminoindoline (265). Reaction of... 

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