Synthesis and Catalytic Activity of (eta~6-p-Cyniene)(phosphane)ruthenium(II) Complexes Supported on Poly(biphenoxyphosphazene) or Chiral Poly(binaphthoxyphosphazene) Copolymers

摘要

The polyphosphazene random copolymer containing di-phenylphosphane ligands {[NP(OC_6H_4PPh_2)_2]_(0.4)[NP(O_2C_(12)-H_8)]_(0.6)}_n (la) (O_2C_(12)H_8=2,2'-dioxy-l,l'-biphenyl),andthe chiral binaphthoxy analogues {[NP(OC_6H_4PPh_2)_2]_(0.1)- [NP(O_2C_(20)H_(12))]_(0.9))_n [O_2C_(20)H_(12)=(R)-2,2'-dioxy-l,l'-binaph-thyl] (1b) and {[NP(OC_6H_4PPh_2)_2]_(0.2)[NP(O_2C_(20)H_(10)Br_2)]_(0.8)}_n[O_2C_(20)H_(10)Br_2=(R)-2,2'-dioxy-6,6'-dibromo-l,l'-binaphthyl] (Ic),reacted in dichloromethane at room temperaturewith appropriate amounts of the dimeric complex [Ru- (eta~6-p-cymene)Cl(mu-Cl)]_2 to give the corresponding polymeric (phosphane)Ru~(II) complexes ([NP(OC_6H_4PPh_2[RuCl-2(eta`6-p-cymene)]_x)_2]_(0.4)[NP(O_2C_(12)H_8)]_(0.6)}_n [x=0.5 (2a),1 (2b)],{[NP(OC_6H_4PPh_2[RuCl_2(eta~6-p-cymene)])_2]_(0.1)[NP(O_2C_(20)-H_(12))]_(0.9))_n (3) and [NP(OC_6H_4PPh_2[RuCl_2(eta~6-p-cymene)])_2]_(0.2)[NP(O_2C_(20)H_(10)Br_2)]_(0.8))_n (4).The isolated products are soluble reddish solids,and are thermally very stable with very high glass transition temperatures.The reaction of 1b or 1c with the cationic precursor [RuCl(PPh_3)_2(eta~6-p-cy-mene)][PF_6] in refluxing THF gave the crosslinked insoluble cationic polymeric complexes {[NP(OC_6H_4PPh_2)_2]_(0.1)[NP- (O_2C_(20)H_(12))]_(0.9)[RuCl(eta~6-P-cymene){PF_6)]_(0.05))_n (5) and [NP-(OC_6H_4PPh_2)_2]_(0.2)[NP(O_2C_(20)H_(10)Br_2)]_(0.8)[RuCl(eta~6-p-cymene)-(PF_6)]_(0.08))_n (6).All the complexes were active catalysts in transfer hydrogenation of acetophenone by propan-2-ol,but the C_2-pockets containing the catalytic centers gave no en-antioselectivity because of the conformational behavior of the chiral derivatives.