ON HETEROCYCLIC-SYSTEMS CONTAINING BISMUTH(III) .2. 8-MEMBERED HETEROCYCLES CL BR/I-M(CH2CH2CH2)(2)X WITH LEWIS ACIDIC GROUP 15 ATOMS M =AS, SB, BI AND DONOR ATOMS X=NR, S - A CONTRIBUTION TO THE VALUE OF THE ELECTRONEGATIVITY OF BISMUTH(III)/
E. Brau et al., ON HETEROCYCLIC-SYSTEMS CONTAINING BISMUTH(III) .2. 8-MEMBERED HETEROCYCLES CL BR/I-M(CH2CH2CH2)(2)X WITH LEWIS ACIDIC GROUP 15 ATOMS M =AS, SB, BI AND DONOR ATOMS X=NR, S - A CONTRIBUTION TO THE VALUE OF THE ELECTRONEGATIVITY OF BISMUTH(III)/, Polyhedron, 13(3), 1994, pp. 365-374
Paths to the ligands (Cl/Br-CH2CH2CH2)(2)NR/O/S/Se, R = Me, Bz, iPr, i
Bu, to the diGrignard reagents (Cl/BrMg-CH2CH2CH2)(2)NR/O/S, R = Me, B
z, iPr, iBu and to the eight-membered group 15 heterocycles (C1/Br/I-A
s/Sb/Bi(CH2CH2CH2)(2)NR/S, R = Me, Bz, iBu are given. C-13-NMR, TR and
Raman spectra are discussed; for the compound ClSb(CH2CH2CH2)(2)NMe t
he crystal structure analysis is given: the antimony atom is clearly L
ewis acidic with psi-trigonal-bipyramidal coordination and a transannu
lar Sb ... N interaction of 2.385(2) Angstrom. For such a configuratio
n the values of the C-13-NMR chemical shifts of the alpha-CH2-groups (
e.g. Cl-As/Sb/Bi(alpha CH2CH2CH2)(2)NMe 34.6, 25.9, 46.6 ppm) display
clearly a sequence N > Bi > P approximate to As > Sb for the Paulins e
lectronegativities of the group 15 elements: a value as high as 2.3 fo
r bismuth is suggested.