Nucleophilicity of Ligated S₂^2-Ions. Conversion of Organic Chlorides into Organosulfur Compounds incis-[(MCp*)₂(μ-CH₂)₂(μ-S₂R)]⁺(M = Rh, Ir)

Abstract

The chemically active rhodium complex cis-[(RhCp*)2(μ-CH2)2(μ-SS)], 1, activated all C−Cl bonds of polychlorinated organic compounds, namely, C6H5CCl3 and p-ClC6H4CCl3 (except ring chlorine), and formed compounds cis-[(RhCp*)2(μ-CH2)2(μ-S2C-C6H5)][BPh4], 6, and cis-[(RhCp*)2(μ-CH2)2(μ-S2C-C6H4-Cl-p)][BPh4], 7, after treatment with NaBPh4. Similarly, the iridium complex cis-[(IrCp*)2(μ-CH2)2(μ-SS)], 2, activated C−Cl bonds of p-ClC6H4-CCl3(except ring chlorine) and formed the compound cis-[(IrCp*)2(μ-CH2)2(μ-S2C-C6H4-Cl-p)][BPh4], 5. Compound 6 is analogous to cis-[(IrCp*)2(μ-CH2)2(μ-S2C−C6H5)][BPh4], 3 (obtained by reaction of 2 with C6H5CHCl2 or C6H5CCl3); however, reaction with C6H5CH2Cl formed the S-benzylated product cis-[(IrCp*)2(μ-CH2)2(μ-SS-CH2-C6H5)][BPh4], 4. Interestingly, compound 2 activated all the C−Cl bonds of CCl4 in methanol and formed the products cis-[(IrCp*)2(μ-CH2)2(μ-S2CH)][BPh4], 8, and [Ir4S4(Cp*)4(μ-CH2)4] [BPh4]2, 9. The unique reactivity of the bridged S2-dimer is that activation of C−Cl bonds occurs at S-donor atoms and not at the usual metal centers.

Construction of trinuclear iridium clusters through ancillary ortho-carborane-1,2-diselenolato ligands, with simultaneous iridium-induced B–H activation

“…5 Molecular structure of 6 with atom labeling, all hydrogen atoms omitted for clarity. Selected bond lengths (A ˚) and angles ( • ): Ir(1)-Se(1) 2.4868 (10), Ir(1)-Se(2) 2.4676 (10), Ir(1)-Se(4) 2.5247 (11), C(1)-C(2) 1.589 (11), B(3)-Ir(2) 2.102 (10), Se(1)-Ir(2) 2.4893 (11), Se(2)-Ir(2) 2.5506 (10), Ir(2)-Se(3) 2.4251 (11), Ir(2)-Se(4) 2.5485 (11), Ir(2)-Se(5) 2.4272(9), C(3)-C(4) 1.674 (12), B(16)-O(1) 1.362 (13), O(1)-C(7) 1.409 (12), Se(3)-Ir(3) 2.4967 (10), Ir(3)-Se(5) 2.4731 (11), C( 5 The molecular structure of 7 is shown in Fig. 6.…”

“…The complexes were characterized by IR, NMR, and X-ray crystallographic analysis. In the reaction, metal- 1) 2.3710 (11), Ir(1)-Se(2) 2.3762 (11), C(1)-C(2) 1.594 (10), C(1)-B(3) 1.780( 14), C(1)-B( 6) 1.798 (12), C(2)-B(3) 1.763( 14), C(2)-B( 6) 1.780( 13), B(3)-O(1) 1.377 (14), O(1)-C(3) 1.305( 11), B(6)-O(2) 1.366 (12), O(2)-C( 4…”

“…), 4.36 (m, 8 H, cod(olefin)). 11 B NMR (CDCl 3 ): d = −3.4, −6.9, −10.3, −12.8, −18.9, −22.6. IR (KBr disk): 2576 cm −1 (m B-H ).…”

“…Fig.5Molecular structure of 6 with atom labeling, all hydrogen atoms omitted for clarity. Selected bond lengths (A ˚) and angles ( • ): Ir(1)-Se(1) 2.4868(10), Ir(1)-Se(2) 2.4676(10), Ir(1)-Se(4) 2.5247(11), C(1)-C(2) 1.589(11), B(3)-Ir(2) 2.102(10), Se(1)-Ir(2) 2.4893(11), Se(2)-Ir(2) 2.5506(10), Ir(2)-Se(3) 2.4251(11), Ir(2)-Se(4) 2.5485(11), Ir(2)-Se(5) 2.4272(9), C(3)-C(4) 1.674(12), B(16)-O(1) 1.362(13), O(1)-C(7) 1.409(12), Se(3)-Ir(3) 2.4967(10), Ir(3)-Se(5) 2.4731(11), C(5)-C(6) 1.655(12); Se(2)-Ir(1)-Se(1) 80.54(4), Ir(2)-Se(1)-Ir(1) 83.97(3), C(1)-B(3)-Ir(2) 98.7(5), B(3)-Ir(2)-Se(1) 76.4(3), Se(3)-Ir(2)-Se(4) 94.37(3), Se(1)-Ir(2)-Se(2) 78.90(3), Se(3)-Ir(2)-Se(5) 83.08(3), B(16)-O(1)-C(7) 124.0(9), Se(6)-Ir(3)-Se(5) 90.75(3), Se(5)-Ir(3)-Se(3) 80.70(3).…”

15 Noble metals

“…This unique reactivity of the bridged S 2 dimer appears to occur at the S-donor atoms and not at the metal centres as would be anticipated. 167 The benzaldehyde functionalized phosphane Ph 5 :g 1 -3-L}Me]BF 4 , having metal-centred chirality, in good yields. When a bulkier substituent was used, the complexes were obtained with higher diastereoselectivity; with an optically active substituent, complete stereodiscrimination at the rhodium centre occurred.…”