PREPARATION, B-11-NMR, C-13-NMR, H-1-NMR AND VIBRATIONAL-SPECTRA OF 1,2-TRIMETHYLENEPENTAHYDRO-CLOSO-HEXABORATE(1-), CIS-[B6H5(CH2)(3)]-, AND 1,2-TETRAMETHYLENEPENTAHYDRO-CLOSO-HEXABORATE(1-), CIS-[B6H5(CH2)(4)]-, AND THE CRYSTAL-STRUCTURES OF [P(C6H5)(4)] [B6H5(CH2)(3)] AND [P(C6H5)(4)][B6H5(CH2)(4)]

By reaction of [B6H6](2-) With diiodopropane or diiodobutane in dichlo romethane the 1,2-trimethylene-pentahydro-closo-hexaborate(1-), cis-[B 6H5(CH2)(3)(-)], and the 1,2-tetra methylene-pentahydro-closo-hexabora te(1-), cis-[B6H5(CH2)(4)](-) are obtained, respectively. The compound s were separated from excess [B6H6](2-) by ion exchange chromatography on diethylaminoethyl cellulose. The crystal structures of [P(C6H5)(4) ][B6H5(CH2)(3)] (I) and [P(C6H5)(4)][B6H5(CH2)(4)] (II) have been dete rmined by single crystal X-ray diffraction analysis: I is triclinic, s pace group P (1) over bar with a = 7,388(2), b = 12,254(2), c = 14,415 (2) Angstrom, a = 85,638(12)degrees, beta = 84,06(2)degrees, gamma = 8 5,13(2)degrees; II is monoclinic, space group P2(1)/c with a 9,7855(10 ), b = 11,0793(10), c = 25,2386(10) Angstrom, beta = 92,491(10)degrees . The B-11 NMR spectra of both compounds reveal the feature of a cis-d isubstituted octahedral B-6 cage. The C-13 NMR spectrum of I exhibits a quartet at 15,46 ppm with (1)J(C,B) = 121,7 Hz (B-CH2) and a triplet at 37,98 ppm with (1)J(C,H) = 124,4 Hz (CH2). For II a quartet at 12, 89 ppm with (1)J(C,B) = 105,5 Hz (B-CH2) and a triplet at 30,00 ppm wi th (1)J(C,H) = 124,4 Hz (CH2) are observed. In the H-1 NMR spectrum of I two multiplets at 0,73 and 1,90 ppm of the CH2 groups and two singl ets at 2,23 and -3,71 ppm of the BH fragments are observed; the signal s of the CH2 groups of II are at 0,60 and 1,35 ppm and of the BH fragm ents at 2,15 and -4,81 ppm, respectively. The IR and Raman spectra exh ibit five very strong CH stretching bands between 2807 and 2938 cm(-1) in case of I and between 2817 and 2889 cm(-1) in case of II.