Synthesis and Characterization of Some New Tetraaldehyde and Tetraketone Derivatives and X-ray Structure of 1,1′-(4,4′-(2-(1,3-bis(4-Acetylphenoxy)propan-2-ylidene)propane-1,3-di-yl)bis(oxy)bis(4,1-phenylene))diethanone

Tetraketone and tetraaldehyde derivatives 2a–d were synthesized via the reaction of ethene-1,1,2,2,-tetra-yl-tetramethylene tetrabromide (1) with hydroxyketone and aldehyde derivatives. The molecular structures were identifed by IR, 1H-NMR, 13C-NMR and MS analysis. The crystal structure of the title compound 2a, C38H36O8, is reported. Its crystal data are: monoclinic, space group P 2(1)/n with cell dimensions of a=9.0395(12) Å, b=12.6114(17) Å, c=13.8166(18) Å, β=95.875(3), V=1566.8(4) Å3, F.W.=620.67, ρcalc=1.316 gcm3 for Z=2, μ=0.092 mm−1


Introduction
Acetophenone (AP, phenylmethylketone or hypnone) is used in consumer fragrances and as an industrial solvent [1]. Acetophenone and its derivatives are important compounds for obtaining biologically active compounds. In general, acetophenones are an important constituent of effective therapeutics against mycobacteria [2]. Acetophenones are used to obtain benzofuran, and its ketoxime derivatives show antifungal activities [3]. In adddition, acetophenones which contain halogens are used to synthesize disubstituted 1,3-thiazole compounds that have selective human adenosine A3 receptor antagonist [4] as well as antifungal and antibacterial activities. Some acetophenone derivatives have antimicrobial activity against gram-positive bacteria and fungi [5] while others are used as herbicides [6]. Certain acetophenones carrying a hydroxyl group at C-2 have antimutagenic activity in Salmonella typhimurium [7]. Many acetophenones are found as natural products in plants [8] and fungi [9]. The oral administration of Paeonol (2-hydroxy-4-methoxy acetophenone) to rats is followed by rapid excretition in the urine as its sulphated derivative [10]. Some acetophenone semicarbazone and acetophenone oxime derivatives are used to obtain biologically active industrial polimers [11]. o-Hydroxyacetophenone oxime is an important analytical reagent for the gravimetric and colorimetric estimation of transition metals [12]. Acetophenone derivatives are very interesting model compounds as foreign substrates for biotransformation, because an enantiomer may be formed, which can be determined easily. These compounds have been effectively used as a building blocks for the asymmetric synthesis of drugs [13].
In a part of our study, we aimed to enhance the selectivity of these macromolecular compounds and the stability of the Schiff base formed with both various amines and heterocyclic moiety. So, we prepared macromolecular compounds having aldehyde and ketone functions connection by flexible bridge. In this study, tetraaldehyde and tetraketone derivatives 2a-d were obtained from the reaction with ethene-1,1,2,2-tetra-yl-tetra methylene tetra bromide (1) with hydroxyaldehydes and hydroxyketones.

Materials
Melting points were determined on a Gallenkamp melting point apparatus and are uncorrected. 1 H-NMR and 13 C-NMR spectra were recorded on a Varian-Mercury 200 MHz spectrometer. The IR spectra were measured as potassium bromide pellets using a Perkin-Elmer 1600 series FTIR spectrometer. The MS spectra were determined on a Micromass Quatro LC/ULTIMA LC-MS spectrometer. Elemental analyses was carried out on a C,H,N-O rapid elemental analyzer Hewlett-Packard 185 for C, H and N and results are with in 0.4 % of the theoretical values. All the chemicals were obtained from Fluka Chemie AG Buchs (Switzerland). Compound 1 was synthesized using the published methods [14].

Crystallographic structure determination compound 2a
A summary of the key crystallographic information is given in Table 1. The data was collected on a smart [15] CCD diffractomer using graphite-monochromated Mo Kα radiation at room temperature. The collected data were reduced by using the program SAINT [15] and empirical absorption correction was carried out by using the SADABS [16] program. The structure was solved by direct methods [17] as implemented in the SHELXTL system of computer programmes and refined to convergence by full matrix least-squares methods. H atoms were located geometrically and then refined isotropically with fixed displacement parameters. Atomic scattering factors used were those from the International Table  for x-ray crystallography [18]. The crystal structure has been deposited at the Cambridge Crystallographic Data Center with the deposition number CCDC 686161.

Results and Discussion
The reaction of ethene-1,1,2,2-tetra-yl-tetramethylene tetra-bromide (1) in absolute ethanol media with the corresponding potassium salts of phenolic ketones and aldehydes (obtained by potassium hydroxide solution) gave the corresponding tetraketones 2a,b or tetraaldehydes 2c,d in a good yield (Scheme 1). The substitution reactions were highly selective for the tetrasubstituted products 2, as independent of the molar ratios of ketophenol or aldehydophenol. Mono-, di-or trisubstituted products could not be obtained in this reaction. In the IR spectra of compounds 2a-d, one sharp absorption band was seen at 1652-1698 cm -1 which is assigned to the carbonyl functions. The CHO Fermi doublet stretching frequency was observed at 2796-2894 cm -1 in the IR spectra of compounds 2c,d.  [21]]. The molecular conformation is essentially described by torsion angles about the C10-C9 and C10-C11 bonds. The C10-C11-O3-C12 and C10-C9-O2-C8 torsion angles are -173.0(2) o and 159.8 (2)

Conclusions
In order to investigate the influence of the flexibility of the ligand molecule, four new carbonyl compounds have been synthesized and the crystal structure of compound 2a was determined. Alkenetetrayltetra oxyphenylaldehyde and tetraketones were obtained by reaction four different hydroxyketones or hydroxyaldehydes and ethene-1,1,2,2-tetra-yl-tetramethylene tetra-bromide (1). So, we successfully prepared C=O functionalized chelates having ether bridges as a key intermediate for the synthesis of novel macromolecules containing a donor group. The compounds were prepared and identified by elemental analysis, IR, 1 H-NMR, 13 C-NMR and Mass spectroscopy. In addition, the crystal structure of the compound 2a, C 38 H 36 O 8 , was determined by single crystal X-ray diffraction technique, figure 1.