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S. Gupta J. K. Ray K. Chinnakali H.-K. Fun 《Acta Crystallographica. Section C, Structural Chemistry》1999,55(2):IUC9900012-IUC9900012
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The synthesis of (S,S)-1,2-bis(3,5-di-tert-butylphenyl)ethane-1,2-diol (98.6% ee), which should be useful as a chiral ligand of catalysts in asymmetric inductions, is described. 相似文献
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B. Riegel H.-D. Hausen W. Schwarz G. Heckmann H. Binder E. Fluck A. Dransfeld P. V. R. Schleyer 《无机化学与普通化学杂志》1996,622(9):1462-1470
1,2-Bis(dimethylamino)-3,4,5-triphenyl-3,4,5-triphospha-1,2-diborolane and 1,2-Bis(dimethylamino)-3,4,5,6-tetra-tbutyl-3,4,5,6-tetraphospha-1,2-diborine: Synthesis and Structure as well as Calculations on the Molecular Structure The diphosphides K2[(C6H5)P? (C6H5)P? P(C6H5)], 4 or K2[(tBuP)? (tBuP)2? P(tBu)], 5 , react with (ClBNMe2)2 to form the binary 5-membered ring system 1,2-bis(dimethylamino)-3,4,5-triphenyl-3,4,5-triphospha-1,2-diborolane (C6H5P)3(BNMe2)2, 2a , and the 6-membered ring system 1,2-bis(dimethylamino)-3,4,5,6-tetra-tbutyl-3,4,5,6-tetraphospha-1,2-diborine, (tBuP)4(BNMe2)2, 3a , respectively. 2a and 3a could be obtained in a pure form and characterized NMR spectroscopically and by X-ray structure analyses. The two ring systems are folded; 2a exists in the ?envelope”?- 3a in the ?boat”?-conformation. Ab initio computations for 3,4,5-triphospha-1,2-diborolane M5 show that the global minimum is characterized by one B? P double bond. The parent compound geometry M6 is characterized by transannular bonding in the PH? BH? BH? PH moiety which differs in character from those in the four- and five-membered rings (BH)2(PH)2 and (BH)2(PH)3 M5 d , respectively. Explicit calculation of the influence of amino substituents on boron improved agreement of the bond length between computed and X-ray data. 相似文献
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以6,9-二乙腈十硼烷和1,4-二乙酰氧基-2-丁炔为原料,合成了高纯度的1,2-二乙酰氧甲基碳硼烷,产率81.2%,纯度96.2%,其结构经UV-Vis,<'1>H NMR,<'11>B N-MR,IR和元素分析表征. 相似文献
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