In:
Zeitschrift für anorganische und allgemeine Chemie, Wiley, Vol. 647, No. 11 ( 2021-06-11), p. 1152-1164
Abstract:
Tungsten Fischer ethoxy‐ and dimethylaminocarbene complexes [W{C(X)(C 6 H 4 ‐4‐R}(CO) 5 ] (X=OEt: series a ; or X=NMe 2 : series b ) are synthesized from phenyl substrates containing remote tertiary amino substituents R’ 2 N with R’=Me ( 2 ), Ph ( 3 ) or C 6 H 4 Br‐4 ( 4 ). The π‐delocalization and carbene‐stabilizing effects of the distant tertiary amine donor substituent are investigated by NMR and IR spectroscopy, electrochemistry and quantum chemical calculations. A significant transfer of electron density from the remote 4‐R’ 2 N substituent to the carbene C atom in the ethoxycarbene complexes is supported by NMR data and the solid‐state structure of 2 a . This is strongly attenuated in the amino‐substituted carbene complex 2 c and irrelevant in the dimethylaminocarbene complexes of series b , where the electron demand of the electrophilic carbene center is satisfied by the directly attached dimethylamino substituent. Quantum chemical calculations and IR spectroelectrochemistry on complexes 1 a‐ ‐ 4 a verify carbene‐centered reductions and a ligand based oxidation of complex 2 b .
Type of Medium:
Online Resource
ISSN:
0044-2313
,
1521-3749
DOI:
10.1002/zaac.v647.11
DOI:
10.1002/zaac.202100081
Language:
English
Publisher:
Wiley
Publication Date:
2021
detail.hit.zdb_id:
201094-X
detail.hit.zdb_id:
1481139-X
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