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Syntheses, Structures and Electronic Properties of Cationic Hydroxy‐ and Methoxy‐Substituted Tricarbonyl(tetracyclopropylcyclopentadienyl)iron Complexes
Author(s) -
Emme Ingo,
Labahn Thomas,
de Meijere Armin
Publication year - 2006
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/ejoc.200500436
Subject(s) - chemistry , cationic polymerization , protonation , crystal structure , alkylation , stereochemistry , medicinal chemistry , crystallography , catalysis , polymer chemistry , organic chemistry , ion
Tetracyclopropylcyclopentadienone, upon liberation from its previously known tricarbonyliron complex 3 , undergoes rapid [4+2] cyclodimerization to the highly congested1,2,4,5,6,7,8,9‐octacyclopropyltricyclo[5.2.1.0 2,6 ]deca‐4,8‐diene‐3,10‐dione ( 6 ) which was characterized by an X‐ray crystal structure analysis. Upon alkylation of 3 with Me 3 OBF 4 as well as protonation with HBF 4 or CF 3 SO 3 H, the remarkably stable cationic tricarbonyl(tetracyclopropylcyclopentadienyl)iron complexes 9 , 10 and 11 , 12 , respectively, were obtained in high yields (91, 87 and 74, 79 %, respectively). X‐ray crystal structural data for 11 and 12 as well as NMR‐ and IR spectroscopic evidences for all four new complexes 9 – 12 indicate that their positive charge predominantly rest on the tricarbonyliron fragments. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)