The synthesis and structural investigations are presented of molybdenum(0) Fischer carbene complexes with general formula [L(CO) 4 MoC(OEt)(Ar)] with L = CO, PPh 3 , AsPh 3 and Ar = 2-thienyl, 2-furyl, 2-(N-methyl)pyrrolyl, 2,2'-bithienyl. The X-ray crystal structures, along with NMR and IR spectroscopy, revealed a cis-orientation of the carbene and pnictogen ligands (PPh 3 or AsPh 3) for all the substituted complexes. A density functional theory study of all possible conformers indicated, in agreement with experimental results, that the cisisomers (PPh 3 or AsPh 3 cis relative to the carbene ligand) are more stable than the corresponding trans-isomers, and that most stable conformers have the aryl group syn to the ethoxy group for Ar = 2-thienyl, 2-(N-methyl)pyrrolyl, 2,2'-bithienyl and anti to the ethoxygroup for Ar = 2-furyl.
Highlights• Structure of cis triphenylarsine-substituted tungsten(0) Fischer-type carbenes.• W-C bond trans AsPh 3 < W-C bond trans carbene < W-C bond trans CO.• Trans-influence for tetracarbonyl W(0)-carbenes: CO > PPh 3 > AsPh 3 .
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.