Synthesis of Group 4 transition-metal complexes bearing a secondary phosphine pendant cyclopentadienyl ligand

• Published in: Journal of organometallic chemistry Vol. 648; no. 1; pp. 231 - 236
• Main Authors: Ishiyama, Takeshi, Nakazawa, Hiroshi, Miyoshi, Katsuhiko
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.2002
• Subjects: Group 4 transition metal; Phosphine pendant cyclopentadienyl ligand; Secondary phosphine; Sulfide complex; Phosphine pendant cyclopentadienyl ligand; Group 4 transition metal; Secondary phosphine; Sulfide complex
• ISSN: 0022-328X; 1872-8561
• DOI: 10.1016/S0022-328X(01)01473-5

Reactions of some chlorides of the Group 4 transition metals were examined with secondary phosphine pendant cyclopentadienyl derivatives, XC 5H 4CH 2CH 2PHR (X=Li, SiMe 3, Sn( n-Bu) 3; R=2,4,6-trimethylphenyl (Mes), 2,4,6-tri- i-propylphenyl (Tip), 2,4,6-tri- t-buthylphenyl (Mes*)). Although reactions of MCl 4 (M=Zr, Hf) did not yield (C 5H 4CH 2CH 2PHR)MCl 3, reactions of MCl 4(SR′′ 2) 2 (SR′′ 2=SMe 2, tetrahydrothiophene) gave (C 5H 4CH 2CH 2PHR)MCl 3(SR′′ 2) n ( n=1, 2). The steric bulkiness of the substituent (R) on the secondary phosphine affects the coordination mode of the phosphine moiety in solution. When R is Mes, the phosphine-coordinated species is stable, when R is Tip, the phosphine-coordinated and -dissociated species are in equilibrium, and when R is Mes*, only the phosphine-dissociated species is observed. Reactions of some chlorides of the Group 4 transition metals were examined with secondary phosphine pendant cyclopentadienyl derivatives and it was found that MCl 4(SR′′ 2) 2 (SR′′ 2=SMe 2, tetrahydrothiophene) reacts with (ER′ 3)C 5H 4CH 2CH 2PHR (ER′ 3=SiMe 3, Sn( n-Bu) 3) to give (C 5H 4CH 2CH 2PHR)MCl 3(SR′′ 2) n (M=Zr, Hf; n=1, 2). The steric bulkiness of the substituent (R) on the secondary phosphine affects the coordination mode of the phosphine moiety in solution.