Metallo 2,3-Disulfidothienoquinoxaline, 2,3-Disulfidothienopyridine, and 2-Sulfido-3-oxidothienoquinoxaline Complexes: Synthesis and Characterization.
The 2,3-disulfidothienoquinoxaline complexes of Cp(2)Mo and dppePd and the 2,3-disulfidothienopyridine complexes of Cp(2)Mo were obtained as products from the S(8) oxidation of the corresponding metallo-1,2-enedithiolate complexes. The analogous 2-sulfido-3-oxidothienoquinoxaline complexes of Cp(2)Ti, Cp(2)Mo, dppPd, and dppePt were prepared from 1-(quinoxalin-2-yl)-2-bromoethanone and the corresponding polysulfido complex. Both Cp(2)Mo{S(2)C(10)H(4)N(2)S} and Cp(2)Mo{SOC(10)H(4)N(2)S} have been characterized crystallographically. These complexes contain an extended planar ring where the metal is bound to substituents at the 2- and 3-positions of the thiophene ring. The oxidation products of the Cp(2)Mo derivatives all have EPR g values near 1.98 and (97/95)Mo hyperfine of </= 8.5 G. All of the complexes have a visible band assigned to an intraligand transition (IL). The excitation of a room-temperature DMSO solution of dppePt{SOC(10)H(4)N(2)S} leads to an emission at 690 nm with a phi = 0.005. Lifetime measurements were best fit as the sum of two exponential decays with lifetimes of 6 and 0.3 ns.
Kaiwar
Sharada P.
SP
Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, and Department of Chemistry, University of Delaware, Newark, Delaware 19711.
Hsu
John K.
JK
Vodacek
Anthony
A
Yap
Glenn
G
Liable-Sands
Louise M.
LM
Rheingold
Arnold L.
AL
Pilato
Robert S.
RS