Construction of the 5,10b-phenanthridine skeleton using [3+2]-cycloaddition of a non-stabilized azomethine ylide: total synthesis of (+/-)-maritidine and (+/-)-crinine alkaloids

TitleConstruction of the 5,10b-phenanthridine skeleton using [3+2]-cycloaddition of a non-stabilized azomethine ylide: total synthesis of (+/-)-maritidine and (+/-)-crinine alkaloids
Publication TypeJournal Article
Year of Publication2011
AuthorsPandey, G, Gupta, NR, Gadre, SR
JournalEuropean Journal of Organic Chemistry
Issue4
Pagination740-750
Date PublishedFEB
ISSN1434-193X
Keywordsalkaloids, Azomethine ylides, Cycloaddition, Natural products, Ylides
Abstract

Vicinal quaternary and tertiary stereocenters of the 5,10b-phenanthridine skeleton 1 are constructed simultaneously in one step by the [3+2]-cycloaddition of non-stabilized azomethine ylide 9, generated by sequential double desilylation of 10 utilizing silver(I) fluoride as a one-electron oxidant. The regioas well as stereochemical origin of this cycloaddition reaction is explained through a favorable transition state 9''. The strategy is successfully applied for the total synthesis of the biologically active alkaloids (+/-)-maritidine (1a), (+/-)-crinine (1b), and their analogues (1d, 1e, and 1f).

DOI10.1002/ejoc.201001263
Type of Journal (Indian or Foreign)Foreign
Impact Factor (IF)3.07
Divison category: 
Organic Chemistry