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The synthesis and structural characterization by IR, ESR, 119 Sn and 57 Fe Mossbauer spectroscopy, X-ray powder diffraction, and TG and DSC methods of a new series of organotin hexacyanoferrates are reported.

Anhydrous [Au2Br6] and Aul can be obtained by halide exchange from [Au2Cl6] with RX (X = Br or I, R = H or alkyl). The addition of [Au2Cl6] to CPh3Cl produces the ionic derivative [CPh3][AuCl4] whose crystal and molecular structure has been determined by X-ray diffraction. Crystal data: space group P21/c, a= 8.225(3), b= 14.671(6), c= 16.738(8)A, β= 97.85(2)° and Z= 4. Other organic chlorides RCl (R = Pr, SiMe3 or But) react with [Au2Cl6] with a partial reduction to the mixed-valence chloride [Au4Cl8]. Addition of [Au2Cl6] to anhydrous iron(III) chloride produced a mass-spectrometrically active mixed iron–gold species.

The addition of p-toluensulfonic acid to alkynyl phenyl selenides is regio- and stereospecific and affords (Z)-α-(phenylseleno)vinyl p-toluensulfonates in good yield. α-(Phenylseleno)vinyl halides are obtained from the reactions of these compounds with magnesium halides. The reactions of (Z)-α-(phenylseleno)vinyl p-toluensulfonates with cyanocuprates afford the corresponding trisubstituted alkenes in which the tosyl group has been selectively substituted by an aryl or an alkyl group with retention of configuration. Finally, the cross coupling reaction of these vinyl selenides with methylmagnesium bromide, in the presence of a nickel catalyst, occurs with retention of configuration and affords the selenium free trisubstituted alkenes.

Benzotriazole and its 5-methyl-and 5-nitro derivatives react with diethyl ethoxymethylenemalonate by ethylation at each of the ring N-atoms and through Michael addition, to give the isomeric esters ethyl (E/Z) 3-[5(6)-R-benzotriazol-1-yl]propenoates. Benzotriazole and its 5-nitro derivative react similarly with ethyl acetoacetate but N-ethyl derivatives are obtained in lower yields. Other 1,2,3-triazoles derivatives and indole were ineffective in this reaction while benzimidazole produced similar results but accompanied with a small amount of a benzimidazoline addition product, whose structure has been determined by crystallo-graphic analysis.

A variety of prop-2-ynylamides have been carbonylated under oxidative conditions to give oxazolines, oxazolines with chelating groups, and bisoxazolines bearing an (alkoxycarbonyl)methylene chain at the 5 position in good yields. The cyclization-alkoxycarbonylation process was carried out in alcoholic media at 50-70 degrees C and under 24 bar pressure of 3:1 carbon monoxide/air in the presence of catalytic amounts of 10% Pd/C or PdI2 in conjunction with KI. Cyclization occurred by anti attack of an oxygen function on the palladium-coordinated triple bond, followed by stereospecific alkoxycarbonylation, strictly resulting in E-stereochemistry. The structures of representative oxazolines and bisoxazolines have been determined by X-ray diffraction analysis.

Transition-metal complexes of 2,3,7,8,12,13,17,18-octamethylcorrole (H3omc) have been prepared in high yield by means of three different synthetic procedures. The macrocycle acts as a trianionic ligand leading to the formation of neutral species. The crystal and molecular structure of the compound [Rh(AsPh3)(omc)] has been determined by X-ray diffraction methods. The crystals are orthorhombic, space group P212121, with unit-cell dimensions a= 20.172(7), b= 12.468(5), c= 14.893(5)A, and Z= 4. The structure was solved by the heavy-atom technique and refined to R= 0.0353 for 1 436 independent reflections. The rhodium atom has a distorted square-pyramidal environment, the basal positions being occupied by the four nitrogen atoms from the corrole ligand and the apex by the arsenic atom from the triphenylarsine molecule.

The crystal and molecular structure of (–)589[(S)s(S)c-Me(EtCHPhCH2)S·HgCl2]2 has been determined by the heavy-atom method from three-dimensional X-ray data collected by counter methods and refined by least-squares techniques to R 0.0468 for 1 207 observed reflections. Crystals are monoclinic, space group P21, with two molecules in a unit cell of dimensions a= 8.457(3), b= 5.634(3), c= 14.667(6)A, and β= 94.68(4)°. The S atom of the donor molecule and the non-bridging Cl(1) atom are strongly bonded to Hg [2.433(4) and 2.315(5)A, respectively]. The overall co-ordination sphere of Hg also includes three crystallographically equivalent bridging Cl(2) atoms [2.677(5), 2.838(10), and 2.995(10)A], and a very weakly π-bonded Ph ring (3.64 A), thus completing an approximately octahedral array. The triply bridging action of Cl(2) leads to the formation of a polymeric structure in which the molecules are linked in chains and further into ribbons parallel to the b axis. l.r. spectroscopic data are consistent with a bent Cl–Hg–Cl moiety. The absolute configuration at both chiral centres of the diastereoisomer is S. The (S)s absolute configuration at the sulphur atom has been correlated with the negative Cotton effect assigned to a charge-trasfer transition at 265 nm in the circular dichroism spectrum. The diastereoselective synthesis of the complex has been confirmed.