The EI mass spectra of seven 1,1'-(3-oxa-pentamethylene)-dicyclopentadienyl lanthanide and yttrium chlorides(1—7),and eleven dicyclopentadienyl lanthanide and yttrium chlorides(8—18) were investigated.Fragmentat...The EI mass spectra of seven 1,1'-(3-oxa-pentamethylene)-dicyclopentadienyl lanthanide and yttrium chlorides(1—7),and eleven dicyclopentadienyl lanthanide and yttrium chlorides(8—18) were investigated.Fragmentation patterns of these complexes were studied by using metastable ion measurements.The EI spectra of complexes 1—7 exhibited strong molecular ion peaks,the frag- mentation of molecular ions were more complicated.The EI mass spectra of complexes 8—18 sup- ported the dimeric structure under gaseous state.In the spectra of dimers(C_5H_5)_3Ln^+·observed were resulted from the skeletal rearrangement involving the migration of cyclopentadienyl moiety.展开更多
Yan-LongBALA, Muhammad D. XIE, Xiao-Min(HUANG, Ji-Ling*Laboratory of Organometallic Chemistry, East China University of Science and Technology, Shanghai 200237, China Benzyl-substituted cyclopentadienyl lanthanide...Yan-LongBALA, Muhammad D. XIE, Xiao-Min(HUANG, Ji-Ling*Laboratory of Organometallic Chemistry, East China University of Science and Technology, Shanghai 200237, China Benzyl-substituted cyclopentadienyl lanthanide complexes were synthesized and characterized by elemental analysis, MS and IR spectroscopy. The analytical data point out the formation of monomeric, unsolvated complexes. In conjunction with Al(Et)3 as co-catalyst, the title complexes are efficient catalysts for the syndiotactic polymeriza-tion of methyl methacrylate. For the complex (C6H5CH2C5H4)2YCl, under the optimum polymerization conditions (60 ℃, n(MMA)∶n(catalyst)∶n(co-catalyst)=1000∶1∶10), a predominantly syndiotactic (rr=66%) polymer of high molecular weight (Mh=105000) was obtained.展开更多
文摘The EI mass spectra of seven 1,1'-(3-oxa-pentamethylene)-dicyclopentadienyl lanthanide and yttrium chlorides(1—7),and eleven dicyclopentadienyl lanthanide and yttrium chlorides(8—18) were investigated.Fragmentation patterns of these complexes were studied by using metastable ion measurements.The EI spectra of complexes 1—7 exhibited strong molecular ion peaks,the frag- mentation of molecular ions were more complicated.The EI mass spectra of complexes 8—18 sup- ported the dimeric structure under gaseous state.In the spectra of dimers(C_5H_5)_3Ln^+·observed were resulted from the skeletal rearrangement involving the migration of cyclopentadienyl moiety.
基金Project supported by the Major State Basic Research Development Program (No. G1999064801) and the National Natural Science Foundation of China (Nos. 20072004 and 29871010).
文摘Yan-LongBALA, Muhammad D. XIE, Xiao-Min(HUANG, Ji-Ling*Laboratory of Organometallic Chemistry, East China University of Science and Technology, Shanghai 200237, China Benzyl-substituted cyclopentadienyl lanthanide complexes were synthesized and characterized by elemental analysis, MS and IR spectroscopy. The analytical data point out the formation of monomeric, unsolvated complexes. In conjunction with Al(Et)3 as co-catalyst, the title complexes are efficient catalysts for the syndiotactic polymeriza-tion of methyl methacrylate. For the complex (C6H5CH2C5H4)2YCl, under the optimum polymerization conditions (60 ℃, n(MMA)∶n(catalyst)∶n(co-catalyst)=1000∶1∶10), a predominantly syndiotactic (rr=66%) polymer of high molecular weight (Mh=105000) was obtained.
