The 9-cyclopentyl-9-borabarbaralane (3e) was obtained by the reaction of K2C8H8 with cyclo-C5H9BCl2. Upon reaction of 3e with acetone, acetaldehyde, ethoxyacetylene, trideuterioacetonitrile, and acetic acid, only products derived from 9-cyclopentyl-9-borabicyclo[4.2.1]nona-2,4,7-triene (1e) were obtained. On the other hand, by methanolysis of 3e, the boronic ester 17 was formed. The tetracyclic borane 18 is proposed as the intermediate. Possible reasons for this unusual chemical behavior are discussed.
ASJC Scopus subject areas
- Organic Chemistry