SYNTHESES, STRUCTURES, AND PROPERTIES OF 2,5-DIHYDRO-1H-1,2,5-PHOSPHADIBOROLES

被引:8
作者
FRANKHAUSER, P [1 ]
DRIESS, M [1 ]
PRITZKOW, H [1 ]
SIEBERT, W [1 ]
机构
[1] UNIV HEIDELBERG,INST ANORGAN CHEM,NEUENHEIMER FELD 270,W-6900 HEIDELBERG,GERMANY
来源
CHEMISCHE BERICHTE-RECUEIL | 1992年 / 125卷 / 06期
关键词
1H-1,2,5-PHOSPHADIBOROLES, DIHYDRO; METAL COMPLEXES;
D O I
10.1002/cber.19921250607
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
Cyclocondensation of the (Z)-1,2-bis[chloro(dialkylamino)boryl]ethenes 6a-c and 1,2-bis[chloro(diisopropylamino)boryl]benzene (8a) with the lithium phosphides Li2P-C6H5, Li2p-C6F5, Li2P-C6H2(tBu)3, [LiPH2 . dmel, and P(SiMe3)3, yields the 2,5-dihydro-1H-1,2,5-phosphadiboroles 1a-c, 2b, c, 3a-c, 4c, 5c, 9a. Compounds 4c, 5c, 9a are characterized by an X-ray structure analysis. Due to the B-N pi-bond, these derivatives are monomeric with little contribution of B-P pi-interaction. However, low-temperature H-1-NMR studies show that the P-inversion barrier is distinct lower (10-15 kcal mol 1) than for PH3 and organophosphanes (ca. 35 kcal mol-1). This may be a result of favorable B-P pi-interaction in the transition state of the inversion at phosphorus. Reaction of the B-methyl-substituted 1,2-bis(chloromethylboryl)benzene (8b) with P(SiMe3)3 gives the 1,2-dihydro-1H-1,2,5-benzophosphadiborole 9b which forms the dimer (9b)2 below 40-degrees-C by an intermolecular B-P acceptor-donor bond. The structure of (9b)2 is confirmed by an X-ray crystal structure analysis. Treatment of 1c with oxygen, sulfur, or selenium leads to the corresponding 1,2,5-chalcogenadiborole derivatives 10, 11 and 12. By this process, the phenylphosphorus group is eliminated as the pentamer (C6H5-P)5 in 25% yield. Reaction of 1c with Me2BBr gives the Lewis acid-base adduct 13 bearing an lambda-3-sigma-4-coordinated phosphorus and one four-coordinated boron atom. Pi-complexation of lc with the (CO)3Fe fragment leads to the iron complex 15 (X-ray diffraction analysis). Deprotonation of 3c with MeLi gives the P-Li-substituted phosphadiborole [3c-H]Li which reacts with Mel, Me2SiCl2, Me3SiCl to form the P-methylated and -silylated derivatives 14a, 14b, 2c. Reaction of 2b with one equivalent of MeOH at -78-degrees-C in pentane does not give the expected P-unsubstituted compound 3b. Instead, B-P ring cleavage is observed with formation of H2P-SiMe3 and (Z)-1,2-bis[(diethylamino)methoxyboryl]ethene.
引用
收藏
页码:1341 / 1350
页数:10
相关论文
共 20 条
  • [1] SYNTHESIS AND CHARACTERIZATION OF THE PHOSPHINIDENE BORATE COMPLEXES [LI(ET2O)2PRBMES2] AND [LI(12-CROWN-4)2][RPBMES2].THF, R=PH, C6H11, OR MES (MES=2,4,6-ME3C6H2) - THE 1ST STRUCTURALLY CHARACTERIZED BORON-PHOSPHORUS MULTIPLE BONDS
    BARTLETT, RA
    FENG, XD
    POWER, PP
    [J]. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1986, 108 (21) : 6817 - 6819
  • [2] BEACHLER RD, 1970, J AM CHEM SOC, V92, P3090
  • [4] Binger P., 1968, ANGEW CHEM, V80, P288
  • [5] SYNTHESIS AND STRUCTURE OF A 2,5-DIHYDRO-1H-1,2,5-PHOSPHADIBOROLE DERIVATIVE
    DRIESS, M
    PRITZKOW, H
    SIEBERT, W
    [J]. ANGEWANDTE CHEMIE-INTERNATIONAL EDITION IN ENGLISH, 1987, 26 (08): : 781 - 782
  • [6] SYNTHESIS, STRUCTURE, AND COMPLEXATION OF 2,2',5,5'-TETRAHYDRO-1,1'-BI(1H-1,2,5-PHOSPHADIBOROLE) DERIVATIVES
    DRIESS, M
    FRANKHAUSER, P
    PRITZKOW, H
    SIEBERT, W
    [J]. CHEMISCHE BERICHTE, 1991, 124 (07) : 1497 - 1503
  • [7] A TETRABORYLPHOSPHONIUM ION WITH A SPIROHETEROCYCLIC STRUCTURE
    DRIESS, M
    FRANKHAUSER, P
    PRITZKOW, H
    SIEBERT, W
    [J]. ANGEWANDTE CHEMIE-INTERNATIONAL EDITION IN ENGLISH, 1989, 28 (02): : 217 - 218
  • [8] SYNTHESIS, STRUCTURE, AND REACTIONS OF 1,2,3,6-TETRAHYDRO-1,2,3,6-DIPHOSPHADIBORINE DERIVATIVES
    DRIESS, M
    PRITZKOW, H
    SIEBERT, W
    [J]. CHEMISCHE BERICHTE, 1989, 122 (03) : 467 - 472
  • [9] DRIESS M, 1989, ANGEW CHEM, V101, P219
  • [10] DRIESS M, 1988, THESIS U HEIDELBERG