PREPARATORY ANALYSIS, B-11 NMR-SPECTROSCOPY, NB-93 NMR-SPECTROSCOPY AND STRUCTURAL-ANALYSIS OF CP2NBBH4 COMPLEXES AND [CPNB(B2H6)] COMPLEXES

被引:31
作者
BRUNNER, H
GEHART, G
MEIER, W
WACHTER, J
WRACKMEYER, B
NUBER, B
ZIEGLER, ML
机构
[1] UNIV REGENSBURG,INST ANORGAN CHEM,UNIV STR 31,W-8400 REGENSBURG,GERMANY
[2] UNIV BAYREUTH,LEHRSTUHL ANORGAN CHEM 2,W-8580 BAYREUTH,GERMANY
[3] UNIV HEIDELBERG,INST ANORGAN CHEM,W-6900 HEIDELBERG,GERMANY
关键词
D O I
10.1016/0022-328X(92)85063-3
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
NbCl5 reacts with NaBH4 and LiCp+ (Cp+ = EtMe4C5) dependent on the stoichiometry and temperature to give Cp+2NbCl2 (1), CP+2Nb2Cl2(B2H6)(2), CP+2NbBH4(3a) and Cp+ 2Nb2(B2H6)2 (4a). With a large excess of NaBH4, Cp+ 2NbCl2 gives 2 at 25-degrees-C, which reacts further with NaBH 4 to give 4a. The synthesis of the deep violet, very stable 4a can be generalised by using C5Me5Li and tBUC5H4Li, respectively. Compounds 1-4 are characterised by means of IR, H-1, and heteroatom NMR spectra. An X-ray structure analysis was carried out with 4a. Whereas 1 and 3 are analogous to already known complexes, in 2 and 4a the B2H, dianion (which is not stable in the free state) is present as a bridging ligand, oriented perpendicularly with respect to the Nb-Nb axis. So far, the highest nuclear magnetic Nb-93 shielding has been observed for compounds 4, extending the range of known delta(Nb-93) values by 2500 ppm. The temperature dependence of the linewidths of both the B-11 and the Nb-93 NMR signals of 4c allows evaluation of the magnitude of J((NbB)-Nb-93-B-11 = 50 +/- 10 Hz.
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页码:313 / 324
页数:12
相关论文
共 33 条
[1]   DIBORANE (6) BRIDGED DIIRON HEXACARBONYL - PREPARATION OF B2H6FE2(CO)6 [J].
ANDERSEN, EL ;
FEHLNER, TP .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1978, 100 (14) :4606-4607
[2]   METALLOCENE SULFIDE CHEMISTRY OF NIOBIUM AND TANTALUM - NEW INSIGHTS INTO THE FORMATION OF NIOBIUM POLYSULFIDO COMPLEXES AND SYNTHESIS, STRUCTURE, AND REACTIVITY OF (CP')2TA(ETA-2-S2)H (CP' = TERT-BUC5H4) [J].
BACH, HJ ;
BRUNNER, H ;
WACHTER, J ;
KUBICKI, MM ;
LEBLANC, JC ;
MOISE, C ;
VOLPATO, F ;
NUBER, B ;
ZIEGLER, ML .
ORGANOMETALLICS, 1992, 11 (03) :1403-1407
[3]   BOROHYDRIDE, HYDRIDE, HALIDE, AND CARBONYL DERIVATIVES OF BIS(PENTAMETHYLCYCLOPENTADIENYL)NIOBIUM [J].
BELL, RA ;
COHEN, SA ;
DOHERTY, NM ;
THRELKEL, RS ;
BERCAW, JE .
ORGANOMETALLICS, 1986, 5 (05) :972-975
[4]  
BERCAW JE, 1982, COMPREHENSIVE ORGANO, V3, P765
[5]   SOLUBLE NIOBIUM POLYSULFIDE COMPLEXES FROM THE REACTION OF (TERT-BUC5H4)2NBH3, (C5ME5)2NBBH4, AND (C5ME5)NB(CO)4 WITH SULFUR [J].
BRUNNER, H ;
KLEMENT, U ;
WACHTER, J ;
TSUNODA, M ;
LEBLANC, JC ;
MOISE, C .
INORGANIC CHEMISTRY, 1990, 29 (04) :584-585
[6]   TITANIUM(IV) AND ZIRCONIUM(IV) TETRAHYDROBORATE MOIETIES SUPPORTED BY A PHENOXO LIGAND [J].
CORAZZA, F ;
FLORIANI, C ;
CHIESIVILLA, A ;
GUASTINI, C .
INORGANIC CHEMISTRY, 1991, 30 (01) :145-148
[7]   BINUCLEAR CHLORO COMPLEXES OF TANTALUM(III) WITH TANTALUM-TANTALUM DOUBLE-BONDS [J].
COTTON, FA ;
NAJJAR, RC .
INORGANIC CHEMISTRY, 1981, 20 (08) :2716-2719
[8]   C-H ACTIVATION - SYNTHESIS OF SILYL DERIVATIVES OF NIOBOCENE AND TANTALOCENE HYDRIDES, THEIR H/D EXCHANGE-REACTIONS WITH C6D6, AND THE STRUCTURE OF CP2TA(H)2SIME2PH [J].
CURTIS, MD ;
BELL, LG ;
BUTLER, WM .
ORGANOMETALLICS, 1985, 4 (04) :701-707
[9]   SYNTHESIS, STABILITY, AND FLUXIONAL BEHAVIOR OF BINUCLEAR MIXED-HYDRIDE TETRAHYDROBORATE COMPLEXES OF HAFNIUM(IV) - X-RAY CRYSTAL-STRUCTURE OF [[(ME2PCH2SIME2)2N]HF(BH4)2](MU-H)3[HF(BH4)[N(SIME2CH2PME2)2]] [J].
FRYZUK, MD ;
RETTIG, SJ ;
WESTERHAUS, A ;
WILLIAMS, HD .
INORGANIC CHEMISTRY, 1985, 24 (25) :4316-4325
[10]   BENT-SANDWICH DERIVATIVES OF TANTALUM BEARING ONE OR 2 PENTAMETHYLCYCLOPENTADIENYL LIGANDS [J].
GIBSON, VC ;
BERCAW, JE ;
BRUTON, WJ ;
SANNER, RD .
ORGANOMETALLICS, 1986, 5 (05) :976-979