In:
Acta Crystallographica Section B Structural Science, International Union of Crystallography (IUCr), Vol. 57, No. 4 ( 2001-08-01), p. 551-559
Abstract:
The H atoms bonded to the chiral C atoms (stereogenic center) of the 1-cyanoethyl groups in two cobalt complexes, [( R )-1-cyanoethyl]bis(dimethylglyoximato)(pyridine)cobalt(III) (2) and [( R , S )-1-cyanoethyl]bis(dimethylglyoximato)(piperidine)cobalt(III) (3), were replaced with D atoms, such as Co—C*D(CH 3 )CN. The crystals of the two cobalt complexes were irradiated with a xenon lamp for 72 h and 27 d, respectively. The unit-cell dimensions were gradually changed with retention of the single-crystal form. The crystal structures after irradiation were determined by neutron diffraction. In each crystal the chiral 1-cyanoethyl group of one of the two crystallographically independent molecules was partly inverted to the opposite configuration, whereas that of the other molecule kept the original configuration. The C*—D bond in the inverted group was completely conserved in the process of the inversion of the chiral alkyl group. This suggests that the inversion of the chiral 1-cyanoethyl group proceeds with the rotation of the cyanoethyl radical after the Co—C bond cleavage by photo-irradiation so that the opposite side of the radical faces the Co atom. This is followed by recombination of the Co—C bond to form the inverted 1-cyanoethyl group.
Type of Medium:
Online Resource
ISSN:
0108-7681
DOI:
10.1107/S0108768101006838
DOI:
10.1107/S0108768101006838/bs0016sup1.cif
DOI:
10.1107/S0108768101006838/bs00162-initialsup2.hkl
DOI:
10.1107/S0108768101006838/bs00162-irradiatedsup3.hkl
DOI:
10.1107/S0108768101006838/bs00162-neutronsup4.hkl
DOI:
10.1107/S0108768101006838/bs00163-initialsup5.hkl
DOI:
10.1107/S0108768101006838/bs00163-irradiatedsup6.hkl
DOI:
10.1107/S0108768101006838/bs00163-neutronsup7.hkl
Language:
Unknown
Publisher:
International Union of Crystallography (IUCr)
Publication Date:
2001
detail.hit.zdb_id:
2020841-8
SSG:
13
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