Novel reactions of various cis-(LC)Mn(CO) 4 complexes (LC ) a three-electron chelating ligand) with diazodiphenylmethane and 9-diazofluorene allowed the synthesis of a new type of oligomeric polynuclear manganospiralene derived from quinoxaline and the ready preparation of a new class of appended (η 5 -fluorenyl)Mn(CO) 3 complexes. Hence, biscyclomanganated 2,3-diphenylquinoxaline cleanly reacted to afford a dinuclear dispiralene in which the heterocycle is embedded between two phenyl rings introduced by diphenyldiazomethane. The reaction of cyclomanganated and rhenated aromatic compounds with 9-diazofluorene is shown to proceed efficiently under thermolytic conditions, which promote the departure of one molecule of CO and the subsequent coordination of a fluorenylidene fragment. Further rearrangements consisting of a cis-migration step and of a series of haptotropic shifts lead to the final appended (η 5 -fluorenyl)M(CO) 3 complex (M ) Mn, Re). This new C-C bond-forming reaction has enabled the synthesis of a pentacyclic helical compound derived from bis-cyclomanganated 2,3-diphenylquinoxaline and whose conformation could be locked by coordination to Ag + , affording a hybrid inorganic-organometallic polyhelix. An overview of the electrochemical properties of selected mono-and binuclear spiralenes is disclosed and shows that most spiralenes display electrochemically reversible reduction processes. An ESR analysis of the radical anion of a dinuclear spiralene indicated that the reduction process is ligand-centered and the spin density essentially located at the heterocycle. The structures of new spiralenes and appended (fluorenyl)M(CO) 3 complexes, obtained by crystal X-ray diffraction techniques, are described.

The thermolytic coupling of Ph(2)CN(2) and (t-Bu)(Ph)CN(2) with doubly cyclomanganated 2,5-diphenylpyrazine and 4,6-diphenylpyrimidine afforded substantial amounts of new triple decker compounds of either C(i) and C(2) symmetry respectively containing, in both series, two eta(3)-bonded Mn(CO)(3) fragments which intervene as scaffolds sustaining the helical non-conjugated triaryl backbone. The molecular structures of two pyrazine derivatives show a typical non-parallel stacking of the aromatic rings and the encapsulation of the central pyrazyl fragment with interplanar centroid-to-centroid distances of ca. 3.5 A. The stacking of the aromatics in the triple-decker pyrimidine derivatives has been assessed by (1)H NMR experiments at low temperature. All the triple-decker-type compounds are electroactive. Pyrimidine triple-deckers can reversibly be electrochemically reduced to the corresponding anions.

ABSTRACT. Vanillin and isobuthyl methyl ketone (4-methylpentan-2-one) reacts under Claisen-Schmidt conditions yielding corresponding dehydrozingerone analogue, (E)-1-(4-hydroxy-3-methoxyphenyl)-5-methylhex-1-en-3-one. A small series of its O-alkyl derivatives was prepared by alkylation of free phenolic group with corresponding alkyl halides. Products had been tested for their biological activity and demonstrated relatively strong in vitro antimicrobial activity towards different strains of bacteria and fungi. All new compounds were well characterized by IR, 1 H and 13 C NMR spectroscopy and physical data.

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F r i e s R e a r r a n g e m e n t i n F e r r o c e n e C h e m i s t r y Abstract: ortho-Ferrocenoylphenol (salicyloylferrocene) has been synthesized and treated with acetyl, propionyl, benzoyl and 2-furoyl chloride to obtain the corresponding (ortho-acyloxybenzoyl)ferrocenes, which were subjected to conditions for the Fries rearrangement. By treatment with AlCl 3 at room temperature in CH 2 Cl 2 they afforded the corresponding heteroanular derivatives, 1-acyl-1¢-(ortho-hydroxybenzoyl)ferrocenes in good to high yield. Under the same reaction conditions, but in the presence of ferrocene, all keto esters gave the corresponding monoacylferrocenes through an intermolecular Fries rearrangement.As a bifunctional ferrocene derivative, (ortho-hydroxybenzoyl)ferrocene [salicyloylferrocene, (1)] might be an interesting intermediate in the synthesis of other derivatives of this metallocene. To our knowledge, there are only two reports about its synthesis in the literature until present. Schaaf 1 synthesized this compound in about 20% overall yield by Friedel-Crafts acylation of ferrocene with o-methoxybenzoyl chloride (prepared in a separate experiment), followed by demethoxylation of the obtained (ortho-methoxybenzoyl)ferrocene. On the other hand, Nesmeyanov and coworkers 2,3 reported that this synthesis can be performed by a direct acylation of ferrocene with salicyloyl chloride (22%). Recently, we found 4 that ferrocene can be transformed into salicyloylferrocene in a one-step process, i.e. by acylation of this metallocene with a mixture of salicylic acid and phosphorus trichloride. Bearing in mind that the phenolic hydroxyl group can be protected/deprotected much more conveniently with an acetyl than with methyl group, we tried to acylate ferrocene with a mixture of acetyl salicylic acid and phosphorous trichloride. However, instead of the expected (ortho-acetoxy-benzoyl)ferrocene (2a) we obtained acetylferrocene (4a) formed in a transacylation process, i.e. an intermolecular Fries rearrangement took place. Because of this finding we decided to synthesize some (ortho-acyloxybenzoyl)ferrocenes in order to subject them the Fries rearrangement. 5,6 Here we report the results of these investigations.First of all, by reinvestigating reaction conditions described by us, 4 we found that the yield of (ortho-hydroxybenzoyl)ferrocene (1) can be improved to 40% by doubling the quantity of AlCl 3 and working with very diluted solutions. Compound 1 was then treated with acetic chloride or acetic anhydride in the presence of pyridine, affording (ortho-acetoxybenzoyl)ferrocene (2a) in almost quantitative yield (see Table 1 and Scheme 1). When ketoester 2a was treated with AlCl 3 in CH 2 Cl 2 at room temperature the reaction mixture became intensive dark violet, similar to the classical acylation of ferrocene by acyl chlorides in the presence of the same catalyst. This color was attributed to the formation of an intermediary complex between a more or less developed acylium cation and the corresponding aluminate, as depicted in the S...