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Structural Studies of [CpMoL 2 (CO) 2 ] + (L = NCMe, L 2 = 2,2′‐biimidazole) Complexes and Their Inclusion Compounds with Cyclodextrins
Author(s) -
Pereira Cláudia C. L.,
Braga Susana S.,
Paz Filipe A. Almeida,
Pillinger Martyn,
Klinowski Jacek,
Gonçalves Isabel S.
Publication year - 2006
Publication title -
european journal of inorganic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 1434-1948
DOI - 10.1002/ejic.200600551
Subject(s) - chemistry , orthorhombic crystal system , crystallography , adduct , protonation , triclinic crystal system , acetonitrile , stoichiometry , crystal structure , thermogravimetric analysis , coordination complex , stereochemistry , metal , ion , organic chemistry
Protonation of [CpMo(η 3 ‐C 3 H 5 )(CO) 2 ] followed by addition of acetonitrile or 2,2′‐biimidazole (H 2 biim) gave the complexes [CpMo(NCMe) 2 (CO) 2 ](BF 4 ) ( 1 ) and [CpMo(H 2 biim)(CO) 2 ](BF 4 ) ( 2 ) in good yields. The structures of 1 and 2 were determined by single‐crystal X‐ray diffraction in the orthorhombic Pbca and triclinic P $\bar {1}$ space groups, respectively. Both complexes have similar metal ion coordination environments, which can be envisaged as slightly distorted pseudo‐square pyramids, a coordination geometry commonly compared with a four‐legged piano stool. The two complexes were immobilised in native and permethylated β‐cyclodextrins (β CD and TRIMEB) by methods tailored according to the stabilities and solubilities of the individual components and this gave four adducts with a 1:1 host/guest stoichiometry. The formation of true inclusion compounds was supported by powder X‐ray diffraction (XRD), thermogravimetric analysis (TGA), 13 C{ 1 H} CP/MAS NMR and FTIR spectroscopy. In the case of the TRIMEB adduct containing complex 1 , the crystal packing arrangement is markedly similar to that previously reported for the corresponding 1:1 TRIMEB adducts of the neutral guests [CpMoX(CO) 3 ] (X = Cl, CH 2 CONH 2 ), featuring columns in which the macrocycles are arranged along the b axis in a tilted fashion.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)