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Title: Alkynes to (Free) Carbenes to Polycyclic Cyclopropanes
ABSTRACT: Carbenes and carbenoids are commonly employed for the synthesis of cyclopropane-containing compounds. Here we report the metal-free, intramolecular cyclopropanation of tethered alkenes by free carbenes derived from alkynes to construct structurally unique, multicyclic cyclopropanes with perfect atom economy. The nature of the tether influences both the rate of carbene formation as well as subsequent competing reaction events. Some of the substrates lead to metastable cyclopropane intermediates that further fragment to furnish interesting isomeric products by mechanistically novel processes. A removable siloxane tether can be utilized to achieve formal intermolecular cyclopropanations and to access cyclopropanol derivatives.  more » « less
Award ID(s):
2155042
PAR ID:
10568548
Author(s) / Creator(s):
; ;
Publisher / Repository:
ACS Publications
Date Published:
Journal Name:
Journal of the American Chemical Society
Volume:
146
Issue:
42
ISSN:
0002-7863
Page Range / eLocation ID:
28642 to 28647
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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