Oxidative Addition of Diphenyldichalcogenides PhEEPh (E = S, Se, Te) to Low-Valent CN- and NCN-Chelated Organoantimony and Organobismuth Compounds

The reactions of the organoantimony(I) compound L 1 4 Sb 4 ( 1 ) (where L 1 = o -C 6 H 4 (CH═NC 6 H 3 ( i- Pr) 2 -2,6)) with diphenyldichalcogenides PhEEPh (E = S, Se, or Te) gave compounds L 1 Sb(EPh) 2 (E = S ( 2 ), Se ( 3 ), Te ( 4 )) as the result of the oxidative addition of the antimony(I) atom across the chalcogen–chalcogen bond. The reaction of diphenyldichalcogenides PhEEPh with an in situ prepared organobismuth(I) compound (via reaction of the parent chloride L 1 BiCl 2 ( 5 ) with two equivalents of KB( s -Bu) 3 H) gave surprisingly diorganobismuth compounds L 1 2 Bi(EPh) (E = S ( 6 ), Se ( 7 ), Te ( 8 )) as the major products along with only a trace amount of the intended compounds L 1 Bi(EPh) 2 (E = S ( 9 ), Se ( 10 ), Te ( 11 )). It turned out that this is the result of instability of 9 – 11 in solution, and their decomposition provided compounds 6 – 8 . The bismuth compounds containing the pincer-type ligand L 2 (L 2 = o,o -C 6 H 3 (CH 2 NMe 2 ) 2 ) containing an extra donor pendant arm were studied with the aim to support their stability by an additional N→Bi interaction. Thus, in situ preparation of the organobismuth(I) compound from L 2 BiCl 2 ( 12 ) and two equivalents of KB( s -Bu) 3 H followed by the addition of PhEEPh gave compounds L 2 Bi(EPh) 2 (E = S ( 13 ), Se ( 14 ), Te ( 15 )). Compounds 13 – 15 showed no tendency for redistribution reaction, contrary to 9 – 11, due to the rigid coordination of both nitrogen donor atoms of the ligand L 2 to the bismuth atom. All studied compounds were characterized by the help of 1 H and 13 C NMR spectroscopy, by elemental analysis, and except compounds 4, 14, and 15 by single-crystal X-ray diffraction analyses.