An easy and direct access to POP-type osmium(II) and osmium(IV) complexes, including OsH 4 {dbf(P i Pr 2 ) 2 } (dbf(P i Pr 2 ) 2 = 4,6bis(diisopropylphosphine)dibenzofuran), is reported. This tetrahydride derivative is an efficient catalyst for the selective formation of imines from alcohols and amines with liberation of H 2 , proving that osmium is a promising alternative to ruthenium for catalysis.
A bimetallic [Ir(3+)]2 complex was synthesized based on a bridging 1,2,3-triazole ligand that coordinates to one Cp*Ir unit as N,N-bidentate chelate, and to the other as a C,C-bidentate ligand. When compared to monometallic homologues, the bimetallic complex shows greatly enhanced product selectivity for the acceptorless dehydrogenation of alcohols; spectroscopic and electrochemical analysis suggest significant alteration of the metal properties in the bimetallic system compared to the monometallic species, which offers a rationale for the observed high selectivity.
Complexes OsCl(3){dbf(P(i)Pr(2))(2)} [1; dbf(P(i)Pr(2))(2) = 4,6-bis(diisopropylphosphino)dibenzofuran], OsCl(3){xant(P(i)Pr(2))(2)} [2; xant(P(i)Pr(2))(2) = 9,9-dimethyl-4,5-bis(diisopropylphosphino)xanthene], and OsCl(3){xant(PPh(2))(2)} [3; xant(PPh(2))(2) = 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene] have been obtained in high yield by the reaction of the corresponding diphosphine with OsCl(3)·3H(2)O. The ruthenium(III) counterparts RuCl(3){dbf(P(i)Pr(2))(2)} (4), RuCl(3){xant(P(i)Pr(2))(2)} (5), and RuCl(3){xant(PPh(2))(2)} (6) are similarly obtained from RuCl(3)·3H(2)O in moderate yields. The X-ray structures of dbf(P(i)Pr(2))(2) and complexes 1-3 are also reported.
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.