THIACYCLOPHANE COMPLEXES OF RHODIUM AND IRIDIUM - SYNTHESIS, STRUCTURE, AND REACTIVITY OF [M(COD)(L)][BF4] (M=RH, IR, L= 2,5,8-TRITHIA[9]-O-CYCLOPHANE (TT[9]OC), 5-OXA-2,8-DITHIA[9]-O-CYCLOPHANE (ODT[9]OC))

The complexes [M(COD)(L)][BF4] (M = Rh, Ir; L = 2,5,8-trithia[9]-o-cyc lophane (TT[9]OC), 5-oxa-2,8-dithia[98-o-cyclophane (ODT[9]OC)) were p repared in acetone by the reaction of [MCl(COD)]2 with 2 equiv each of AgBF4 and L. [Rh(COD)(TT[9]OC)][BF4] (1) crystallized in the space gr oup Pca2(1) with a = 23.951(4) angstrom, b = 8.845(2) angstrom, c = 10 .463(8) angstrom, V = 2217(1) angstrom3, and Z = 4. The structure was refined to R = 5.26% and R(w) = 5.70% for 1192 reflections with F(o)2 > 3sigma(F(o)2). [Ir(COD)(TT[9]OC)] [BF4] (2) crystallized in space gr oup P1BAR with a = 11.085(6) angstrom, b = 12.649(2) angstrom, c = 7.9 65(2) angstrom, alpha = 103.10(l)-degrees; beta = 93.93(1)-degrees; ga mma = 89.45(1)-degrees, V = 1085.2(5) angstrom3, and Z = 2. The struct ure was refined to R = 4.06% and R(w) = 4.41% for 2935 reflections wit h F(o)2 > 3sigma(F(o)2). 1 and 2 have trigonal bipyramidal geometry wi th the benzylic S atoms and an olefinic bond occupying the equatorial sites and the central S atom and the other olefinic bond in the axial positions. (Rh(COD)(ODT[9]OC)][BF4](3) crystallized in the space group P2(1)/c with a = 9.173(2) angstrom, b = 24.173(6) angstrom, c = 9.907 (3) angstrom, beta = 94.14(3)-degrees; V = 2190(2) angstrom3, and Z = 4. The structure refined to R = 5.84 % and R(w) = 6.87% for 2312 refle ctions with F(o)2 > 3sigma(F(o)2). [Tr(COD)(ODT[9]OC)][BF4] (4) crysta llized in the space group P1BAR with a = 9.677(3) angstrom, b = 13.142 (6) angstrom, c = 8.996(2) angstrom, alpha = 107.48(3)-degrees; beta = 92.87(3)-degrees; gamma = 97.46(3)-degrees, V = 1077.2(7) angstrom3, and Z = 2. The structure was refined to R = 7.38% and R(w) = 6.59% for 3802 reflections with F(o)2 > 3sigma(F(o)2). 3 and 4 are square plana r complexes with the benzylic S atoms and olefinic bonds coordinated. Reaction of 1 with CO yielded the complexes [Rh(CO)2(TT[9]OC)][BF4] (5 ) and [(TT[9]OC)Rh(mu-CO)3Rh(TT[9]OC)][BF4]2 (6). 2 was relatively unr eactive toward CO; however, reactions with [IrCl(COE)2]2 yielded [lr(C OE)(CO)(TT[9]OC)][BF4] (7) and [Ir(CO)2(TT[9]OC)][BF4] (8) upon reacti on with TT[9]OC and CO. [lr(COE)(CO)(TT[9]OC][BF4] (7) crystallized in the space group Pbca with a = 23.338(5) angstrom, b = 24.646(9) angst rom, c = 13.805(5) angstrom, V = 7940(4) angstrom3 , and Z = 8. The st ructure was refined to R = 7.68 % and R(w) = 7.98% for 1493 reflection s with F(o)2 > 3sigma(F(o)2). 7 has trigonal bipyramidal geometry simi lar to 2 with the CO group in an axial position. 3 and 4 reacted with CO to yield [Rh(CO)3(ODT[9]OC)][BF4] (9) and [Ir(CO)3(ODT[9]OC)][BF4] (10), respectively. Reactions of 1-4 with NOBF4 yielded the adducts [M (NO)(COD)(L)][BF4]2(11-14). [Ir(NO)(COD)(ODT[9]OC)][BF4]2(14) crystall ized in the space group Pnma with a = 18.821(6) angstrom, b = 9.611(5) angstrom, c = 14.225(8) angstrom, v = 2573(2) angstrom3, and Z = 4. T he structure was refined to R = 5.11% and R(w) = 4.83% for 1180 reflec tions with F(o)2 > 3sigma(F(o)2). 14 has square pyramidal geometry wit h the bent NO group in an apical position.