| Abstract
| - Lithiation of R2P(CH2C9H6N-8)NBut (R = Ph, 3; R = Pri, 4) with an equivalent of BunLi affordedlithium iminophosphorano(8-quinolyl)methanide [Li{CH(8-C9H6N)P(Ph2)NBut}(THF)] (5) and [Li{CH(8-C9H6N)P(Pri2)NBut}]2 (6), respectively. Reaction of 4 with Et2Mg yielded magnesiumiminophosphorano(8-quinolyl)methanide complex (7). Treatment of 6 with ZnCl2 gave [Zn(Cl){CH(8-C9H6N)P(Pri2)NBut}] (8), which was transformed into alkylated zinc complexes [Zn(R1){CH(8-C9H6N)P(Pri2)NBut}] (R1 = Ph, 9; R1 = Me, 10) by treating with R1Li or R1MgX. Ethylzinc complexes[Zn(Et){CH(8-C9H6N)P(R2)NBut}] (R = Ph, 11; R = Pri, 12) were obtained by reaction of 3 or 4 withan equivalent of Et2Zn. Compounds 2 and 4−12 were characterized by 1H, 13C{1H}, and 31P{1H} NMRspectroscopy and elemental analyses. Structures of complexes 6−8 and 10 were further characterized bysingle-crystal X-ray diffraction techniques. The catalytic behaviors of complexes 7 and 9−12 in thering-opening polymerization of ε-caprolactone was studied. Complex 7 exhibited high catalytic activityin the presence or absence of benzyl alcohol. Complexes 9−12 catalyzed the ring-opening polymerizationof ε-CL in the presence of benzyl alcohol and exhibited first-order dependence on monomer concentration.
- Lithium, magnesium, and zinc complexes supported by [CH(8-C9H6N){P(R2)NBut}]- (R = Ph, Pri) ligands have been synthesized and characterized. The catalytic behavior of the magnesium and zinc complexes in the ring-opening polymerization of ε-caprolactone have been evaluated.
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