Accession Number : ADA211280

Title :   Metal Mediated Addition of Carbon Dioxide to the Activated Benzene in (Cr(eta4-C6H6) (CO)3)(2-).

Descriptive Note : Technical rept.,

Corporate Author : PITTSBURGH UNIV PA DEPT OF CHEMISTRY

Personal Author(s) : Corella II, Joseph A. ; Cooper, N. J.

Report Date : 03 AUG 1989

Pagination or Media Count : 15

Abstract : The activated benzene in Creta 4 - C6H6)(CO)3 2- (1 2-) reacts readily with Carbon dioxide to form a cyclohexadienyl Carboxylate formulated as Cr(eta 5-C6H6CO2)(CO)3(2-) (2 2-) on the basis of IR studies. Oxidation with dry oxygen gives the Pi-benzoate complex Cr(eta 6-C6H5CO2) (CO)3(-)(4-), a s confirmed by silylation to give Cr eta6-C6H5CO2SiMe3)(CO)3 (5). Oxygenated Mc3SiCl will convert 2 2- directly to 5 in 45% yield. Direct silylation of 2(2-) gives exclusively the endo isomer of the cyclohexadienyl complex Cr eta 5-C6H6CO2SiMe3)(CO)3(-) (6-), suggesting that 2 (2-) also has an endo configuration and that carboxylation of 1 (2-) therefore involves initial CO2 addition to the metal followed by carboxylate migration to the arena ring.

Descriptors :   *ADDITION REACTIONS, *BENZENE, *CARBON DIOXIDE, ACTIVATION, DRY MATERIALS, OXIDATION, OXYGEN, MOLECULAR COMPLEXES, BENZOATES, SILICON COMPOUNDS, MOLECULAR ISOMERISM, METALS.

Subject Categories : Organic Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE