Palladium/Lewis Acid‐Catalyzed Reactions of Bicyclic Hydrazines with Organostannanes: A General Methodology for the Stereoselective Synthesis of 3,4‐Disubstituted Cyclopentenes

Abstract

Pd/Lewis acid-catalyzed reactions of bicyclic hydrazines with organostannanes afforded the 3,4-disubstituted cyclopentenes in excellent yields. The reaction is milder and is the first general methodology developed for the stereoselective synthesis of trans, vicinal disubstituted cyclopentenes. The results show that organostannanes with easily functionalizable moieties can be efficiently utilized in the ring opening of bicyclic hydrazines leading to the stereoselective formation of 3,4-disubstituted cyclopentenes. The products, having a wide range of substituents, are important intermediates in the synthesis of biologically active molecules like cyclopentenyl nucleosides, glycosidase inhibitors etc.

Desymmetrization of meso-Bicyclic Hydrazines: An Efficient Strategy towards the Synthesis of Functionalized Cyclopentenes

“…It is interesting to note that both the bi-and tricyclic hydrazines gave similar products under the same reaction conditions. 24 The possibility of introducing heteroatom substituents to the cyclopentene core inspired us to evaluate the reactivity of azidostannanes with bicyclic hydrazines. As expected, the reaction afforded 3-azido-4-hydrazinocyclopentenes 37a-d in good to excellent yields (Scheme 16).…”