STERIC AND ELECTRONIC PROBES FOR ALPHA-AGOSTIC INTERACTION IN A NIOBIUM ETHYL COMPLEX

被引：37

作者：

ETIENNE, M ^{[1
]}

机构：

[1] INST NATL POLYTECH TOULOUSE, F-31077 TOULOUSE, FRANCE

来源：

ORGANOMETALLICS | 1994年 / 13卷 / 02期

关键词：

D O I：

10.1021/om00014a004

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The new ethyl complexes Tp'Nb(Cl)(CH2-CH3)(PhC=C-R) (Tp'= hydridotris(3,5-dimethylpyrazolyl)borate; R = CH3, 2a; R = CH2CH3, 2b) are shown to exhibit an alpha-hydrogen agostic interaction. The reason why the alpha-agostic interaction is preferred over a more conventional beta-agostic interaction is proposed to lie on steric grounds. Accordingly, the bulkier benzyl ligand in Tp'Nb(Cl)(CH2Ph)(PhC=CCH3) (3) coordinates in an eta1 fashion, whereas the good pi-donor methoxy ligand in Tp'Nb(OCH3)(CH2CH3)(PhC=CCH3) (4) weakens the alpha-agostic bond.

引用

页码：410 / 412

页数：3

共 24 条

[1] BROOKHART M, 1988, PROG INORG CHEM, V36, P1
[2] C-H ACTIVATION MECHANISMS AND REGIOSELECTIVITY IN THE CYCLOMETALATION REACTIONS OF BIS(PENTAMETHYLCYCLOPENTADIENYL)THORIUM DIALKYL COMPLEXES
BRUNO, JW
SMITH, GM
MARKS, TJ
FAIR, CK
SCHULTZ, AJ
WILLIAMS, JM
[J]. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1986, 108 (01) : 40 - 56
[3] ETA-2-BENZYNE AND ETA-1-BENZYLIDENE COMPLEXES OF NIOBIUM WITH ANCILLARY IMIDO LIGANDS
COCKCROFT, JK
GIBSON, VC
HOWARD, JAK
POOLE, AD
SIEMELING, U
WILSON, C
[J]. JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS, 1992, (22) : 1668 - 1670
[4] COLLMAN JP, 1987, PRINCIPLES APPLICATI
[5] MONOCYCLOPENTADIENYL COMPLEXES OF NIOBIUM(III) AND TANTALUM(III) - STRUCTURES OF [CP'NBCL(CO)2]2(MU-CL)2 AND CP'NBCL2(ARCCAR)(AR=PARA-TOLYL)
CURTIS, MD
REAL, J
KWON, D
[J]. ORGANOMETALLICS, 1989, 8 (07) : 1644 - 1651
[6] INSERTION AND ALKYNE COUPLING REACTIONS ON EARLY-TRANSITION-METAL CENTERS - STRUCTURES OF CPTA(ME)(ETA-2-ARCCAR)(ETA-2-MECNTBU), CPMETAC(PH)C(PH)C(ME)NTBU, AND CPCLMO(CPH)4 (AR = PARA-TOLYL)
CURTIS, MD
REAL, J
HIRPO, W
BUTLER, WM
[J]. ORGANOMETALLICS, 1990, 9 (01) : 66 - 74
[7] SYNTHETIC, STRUCTURAL, AND THEORETICAL-STUDIES OF ETA-2-ACYL COMPLEXES OF MOLYBDENUM
CURTIS, MD
SHIU, KB
BUTLER, WM
[J]. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1986, 108 (07) : 1550 - 1561
[8] AN UNUSUAL EFFECT OF LIGAND METHYL-SUBSTITUTION IN THE REACTION OF TRICARBONYL (GROUP-6A METAL) [HYDROTRIS(3,5-R2-1-PYRAZOLYL)BORATO] ANIONS (R=H, ME) WITH ARENEDIAZONIUM CATIONS - X-RAY CRYSTALLOGRAPHIC CHARACTERIZATION OF A MOII ETA-2-AROYL COMPLEX, (MO(ETA-2-COC6H4ME-PARA) (CO)2(HB(3,5-ME2C3HN2)3)) AND OF AN ETA-2-HEXAHYDROBENZOYL ANALOG, [MO(ETA-2-COC6H11) (CO)2(HB(3,5-ME2C3HN2)3)]IO
DESMOND, T
LALOR, FJ
FERGUSON, G
RUHL, B
PARVEZ, M
[J]. JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS, 1983, (01) : 55 - 56
[9] CARBON-MONOXIDE INSERTION AND COUPLING REACTIONS OF NIOBIUM ALKYNE COMPLEXES
ETIENNE, M
WHITE, PS
TEMPLETON, JL
[J]. ORGANOMETALLICS, 1993, 12 (10) : 4010 - 4015
[10] VERTICAL 4-ELECTRON-DONOR ALKYNE LIGANDS IN (TRIS(3,5-DIMETHYLPYRAZOLYL)BORATO)NIOBIUM COMPLEXES
ETIENNE, M
WHITE, PS
TEMPLETON, JL
[J]. ORGANOMETALLICS, 1991, 10 (11) : 3801 - 3803

← 1 2 3 →