Transition metal complexes with sulfur ligands - Part CXXV. Synthesis and characterization of hydride and chloro complexes with rhodium sulfur cores

Rhodium hydride complexes [Rh(H)(L) ('S-bu(4)')] (L = PMe3 (2a); PCy3 (3a); THT (4); NH3 (5) 'S-bu(4)'(2-) = 1,2-bis(2-mercapto-3,5-di-t-butylphenylthio)ethane(2-)) and [Rh(H)(L)('S-4')] (L = PMe3 (2b); PCy3 (3b); 'S-4'(2-) = 1,2-bis(2-mercapto-phenylthio)ethane(2-)) have been obtained by CO substitution reactions from [Rh(H)(CO)('S-R(4)')] (R = (t)bu (1a); R = H (1b)) and monodentate two electron donors. In the absence of appropriate donors, [Rh('S-bu(4)')](2) (15) and [Rh(H)('S-4')](2) (19) formed. CO substitution in [Rh(Cl)(CO)('S-bu(4)')] (6) by various monodentate two-electron donors yielded the chloro complexes [Rh(Cl)(L)('S-bu(4)')] (L = (t)buSH (7); THT (8); SEt2 (9); PCy3 (10); PMe3 (11a); NH3 (13)). [Rh(PMe3)(2)('S-bu(4)')]Cl (12a) and [Rh(NH3)(CONH2)('S-bu(4)')] (14) were byproducts in the reaction with L = PMe3 and NH3. The chloro complexes 11a, 11b and [Rh(Cl)(PPh3) ('S-4')] (18) were obtained from the hydride complexes 2a, 2b and [Rh(H)(PPh3)('S-4')] (17), respectively, when dissolved in chlorinated hydrocarbons. Reaction of complex 1b with hydrochloric acid or gaseous HCl yielded [Rh-2(H)(Cl)('S-4')(2)] (20) that was cleaved into complex 2b and [Rh(PMe3)(2)('S-4')]Cl (12b) upon addition of PMe3. Complexes 3a, 17 and 18 crystallize in the monoclinic space group P2(1)/c, Z = 4, with a = 14.720(3), b = 15.37(2), c = 27.719(6) Angstrom and beta = 90.98(2)degrees for 3a . 4CH(2)Cl(2), with a = 15.922(3), b = 17.681(4), c = 16.510(5) Angstrom and beta = 115.17(2)degrees for 17 . 3THF, and with a = 10.712(3), b = 20.19(1), c = 20.228(5) Angstrom and beta = 97.87(2)degrees for 18 . 3CHCl(3). Complex 11b . 1/3THF crystallizes in the rhombohedral space group R (3) over bar, Z = 18, with a = b = 25.464(4) and c = 17.69(2) Angstrom. The rhodium centers of all complexes are surrounded pseudo-octahedrally by four S, one P and the H or Cl atom. The distances and the PCy3 conformation in 3a . 4CH(2)Cl(2) indicate H ... H interactions between cyclohexyl CH atoms and the hydride ligand. Complex 15.4.5acetone crystallizes in the monoclinic space group C2/c, Z = 4, with a = 19.817(9), b = 21.134(9), c = 21.51(1) Angstrom and beta = 114.74(5)degrees. Both Rh centers of 15.4.5acetone are surrounded by five S atoms and the neighboring Rh atom to give a distorted octahedron. One of the S(thiolate) donors of each 'S-bu(4)'(2-) ligand bridges both Rh centers. (C) 1998 Elsevier Science S.A. All rights reserved.