Oligophosphan-Liganden: XXXIII. Inter- und intramolekulare Spaltungen von sp2- und sp3-CH-Bindungen an L 4Ru 0-Komplexrümpfen mit P( 0-C 6H 4PMe 2) 3, N(CH 2CH 2PMe 2) 3, MeP(CH 2CH 2CH 2PMe 2) 2/PR 3 und MeSi(CH 2PMe 2) 3/PR 3 (R = Me, OMe) als Stützliganden

Abstract

While attempts at the preparation of complexes of composition (pp 3)RuH(Ar) (pp 3 = P( 0-C 6H 4PMe 2) 3) by reduction of (pp 3)RuCl 2 ( 1) with Na(Hg) in benzene, toluene, and xylenes remained unsuccessful, sodium amalgam reduction of the osmium homologue (pp 3)OsCl 2 ( 2) in C 6H 6 proceeded smoothly at room temperature to afford (pp 3OsH(C 6H 5) (7). The hydrido phenyl derivatives (pp 2)[(MeO) 3P]RuH(C 6H 5) ( 13) and (sip 3)(Me 3P)RuH(C 6H 5) ( 14) (pp 2 = MeP(CH 2CH 2CH 2PMe 2) 2, sip 3 = MeSi(CH 2PMe 2) 3) were similarly obtained by reduction with Na(Hg) of benzene solutions of (pp 2)[(MeO) 3P]RuCl 2 ( 5) and (sip 3)(Me 3P)RuCl 2 ( 6), respectively. Treatment of (np 3)RuCl 2 ( 3) (np 3 = N(CH 2CH 2PMe 2) 3) with sodium amalgam in refluxing benzene afforded a 1 : 4 mixture of (np 3)RuH(C 6H 5) ( 8) and [(Me 2 PCH 2CH 2) 2NCH 2CH 2P(Me)CH 2]R uH ( 9). When the reaction temperature was decreased, the portion of complex 8, formed by intermolecular oxidative CH addition, was observed to increase. Interaction of (pp 2)(Me 3P)RuCl 2 ( 4) with Na(Hg) in mesitylene produced (pp 2)(Me 3P)RuH(CH 2C 6H 3Me 2-3,5) ( 10) together with (pp 2)(Me 2 PCH 2)R uH ( 12), presumably via (pp 2)(Me 3P)Ru 0 and (pp 2Ru 0 as reactive intermediates: Reduction of 4 in 1,3,5-Me 3C 6H 3/PMe 3 (1:1) yielded metallacycle 12 as the only product of CH-cleavage, while (pp 2)(4-MeC 5H 4N)RuH(CH 2C 6H 3 Me 2-3,5) ( 11) was isolated when dichloride 4 was treated with sodium amalgam in mesitylene under a stream of argon (to remove any PMe 3) in the presence of 4-picoline. Cyclometallated (sip 3)(Me 2 PCH 2)R uH ( 15) resulted from Na(Hg) reduction of 6 in p-xylene.