We have synthesized five zinc complexes of molecular formulae [ZnCl
2
(2,6-dimethylphenyl-
BIAO)]
2
(
1a
), [ZnBr
2
(2,6-dimethylphenyl-BIAO)]
2
(
1b
), [ZnI
2
(2,6-dimethylphenyl-BIAO)]
2
(
1c
), [ZnBr
2
(mes-
BIAO)]
2
(
2b)
and [ZnBr
2
(dipp-BIAO)] (
3b)
with rigid unsymmetrical imi
noacenaphthenone ligands, (2,6-
dimethylphenyl-BIAO) (
1
), (mesityl-BIAO) (
2
) and (2,6-diisopropylphenyl-BIAO) (
3
).Thezinccomplex
1a
was prepared by the reaction of ZnCl
2
and neutral (mesityl-BIAO) (
1
). However, complexes
1b
,
2b
and
3b
were
obtained by the treatment of ZnBr
2
and neutral ligands
1
–
3
respectively in 1:1 molar ratio in dichloromethane
at ambient temperature. In a similar reaction of ZnI
2
with (2,6-dimethylphenyl-BIAO) (
1
) in dichloromethane
the corresponding iodo-complex
1c
was obtained in good yield. All the zinc (II) complexes are characterized
by FT-IR,
1
Hand
13
C{
1
H} NMR spectroscopic techniques. The solid state structures of the complexes
1a
,
1b
,
1c
,
2b
and
3b
are confirmed by single crystal X-ray diffraction analysis. The molecular structures of com-
plexes
1a
,
1b
,
1c
and
2b
reveal the dimeric nature of the complexes and subsequently the centre atom zinc is
penta-coordinated to adopt distorted trigonal bipyr
amidal geometry around it. In contrast, the complex
3b
is
in monomeric in nature due to bulkier size of the ligand and zinc ion is tetra coordinated to adopt distorted
tetrahedral geometry
