Pure Appl. Chem., 2011, Vol. 83, No. 9, pp. 1781-1788
http://dx.doi.org/10.1351/PAC-CON-11-01-14
Published online 2011-07-07
Straightforward synthesis of five-membered metallacycloallenes: 1-Zirconacyclopenta-2,3-diene compounds derived from 1,3-enynes
Abstract:
A five-membered metallacycloallene complex, 1-zirconacyclopenta-2,3-diene, was prepared from low-valent zirconocene and 2,4-bis(trimethylsilyl)but-1-en-3-yne. The complex reacted with carbonyl compounds to afford alkynyl alcohols after hydrolysis via C=O insertion into Zr–C bond. Similarly, nitriles inserted into the Zr–C bond to give the corresponding ketones after hydrolysis. The insertion of C=O and CN selectively took place at zirconium-sp3 carbon of the metallacycle.
Keywords
1,3-enynes; 1-metallacyclopenta-2,3-dienes; cycloallenes; metallacycles; zirconium.