Reactivities of organic isothiocyanates and thiocyanates toward dialkyl bis(phosphine) complexes of palladium(II) and platinum(II)
作者:Seon Gye Lee、Keun-Young Choi、Yong-Joo Kim、SuJin Park、Soon W. Lee
DOI:10.1016/j.poly.2014.10.020
日期:2015.1
Room-temperature reactions of trans-[PdEt2L2] (L = PMe3, PEt3, PMe2Ph) with organic isothiocyanates 1R-NCS; R = benzyl; CH(CH3)Ph, R-(-) and S-(+); indanyl, S-(+)] afforded the S,S-coordinated Pd(II) complexes [Pd(S2C=N-R)L-2] containing a dithiocarbonimidato (S2C--,--N-R) group. Similar reactions involving allyl isothiocyanates produced the cationic eta(3)-allyl Pd complex [Pd(eta(3)-allyl)(PMe3)(2)](+)(NCS)(-). When [Pd(S2C=N-R)(PMe3)(2)] was treated with 1 equiv of a chelating phosphine [L-L = depe (1,2-bis(diethylphosphino)ethane) and dmpe (1,2-bis(dimethylphosphino)ethane)1, the corresponding complexes [Pd(S2C=N-R)(L-L)] were produced. Reactions of trans-[PdEt2L2] (L = PMe3, PMe2Ph) with organic thiocyanates (R-SCN; R = benzyl, Et) resulted in the formation of [Pd(CN)(2)L-2] and an organic disulfide by S-C bond cleavage of R-SCN. However, similar reactions of the dimethyl analogs, trans-[PdMe2L2] (L = PMe3, PEt3), with benzyl thiocyanate afforded different products, [Pd(NCS)(2)L-2] or [PdMe(NCS)L-2]. Treating [Pt(styrene)(PMe3)(2)] with benzyl isothiocyanate gave the S-coordinated dithiocarbonimidato Pt(II) complex, [Pt(S2C=N-R)(Me3P)(2)] (R = benzyl). In contrast, cis-[PtEt2(PMe3)(2)] reacted with the isothiocyanate to afford the trialkyl Pt(IV) complex [PtEt2(SCN)(CH2Ph)(PMe3)(2)]. (C) 2014 Elsevier Ltd. All rights reserved.