LAUSR

Abstract The functionalization of 3,5-di- tert -butylcatechol with a group CH 2 X in the 6 th position (where the group X has the additional heteroatoms) was performed in order to prepare new functionalized 3,5-di- tert -butylcatechols of the common type (6-(CH 2 -X)-3,5-Cat)H 2 , where X is methoxy group (catechol 1a , X = OMe), 3,5-dimethylpyrazol-1-yl (catechol 1b , X = Me 2 Pyr) and benzimidazol-1-yl (catechol 1c , X = Benzimid). The oxidation of catechols 1a-1c with K 3 [Fe(CN) 6 ] in alkaline medium leads to new functionalized o -quinones 2a - 2c and corresponding o -benzoquinones of the type 6-(CH 2 -X)-3,5-Q. The molecular structures of pyrazolyl-containing catechol 1b and its o -quinone 2b in crystal were determined by single-crystal X-ray analysis. The treatment of o -benzoquinones with triphenylstibine gives new triphenylantimony(V) catecholates (6-(CH 2 -X)-3,5-Cat)SbPh 3 ( 3a - 3c ) containing additional functional groups in the substituent at the 6 th position of catecholato aromatic ring. The molecular structures of catecholates (6-(CH 2 -OMe)-3,5-Cat)SbPh 3 ( 3a ) and (6-(CH 2 -Me 2 Pyr)-3,5-Cat)SbPh 3 ·H 2 O ( 3b ·H 2 O) in crystal were determined by means of single-crystal X-ray analysis. In crystal, complex 3a forms two geometrical isomers with different position of CH 2 OMe group towards aromatic cycle of catecholato ligand. The “C Ph –H…π-system” interactions between these isomers were found. The coordination environment of the central antimony atom in 3b ·H 2 O is a distorted octahedral with a coordinated water molecule which is involved in the intramolecular hydrogen bonding with pyrazolyl group of catecholato ligand.