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The valence shell electronic structures of methylhydrazine (C[H.sub.3]NHN[H.sub.2]), 1,1-dimethylhydrazine ([(C[H.sub.3]).sub.2]NN[H.sub.2]) and tetramethylhydrazine ([(C[H.sub.3]).sub.4][N.sub.2]) are studied. A linear relationship between the ionization energy of a specific orbital and the inverse of the size of the molecule is shown and neutral and ion heats of formation for methyl-hydrazine, 1,1-dimethylhydrazine and tetramethylhydrazine are obtained from G3 calculations.

High-pressure Diels-Alder reactions of various alkoxy/alkyl-substituted benzylideneacetones with methyl-1,3-butadienes are described. The application to the synthesis of [[DELTA].sup.8]-trans-THC in both enantiomeric pure forms is based on the resolution of selected cycloadduct by the SAMP-hydrazone method.

A practical, chromatography-free preparation of 5-lipoxygenase inhibitor MK-0633 p-toluenesulfonate is discussed. An improved second route has featured an inexpensive diastereomeric salt resolution of vinyl hydroxyl-acid followed by a robust end-game featuring hydrazide aylation/1,3,4-oxadiazole ring closure/salt formation sequence, which has produced MK-0633 p-toluenesulfonate.

The reactivity of hydrazones toward molecular oxygen, with regard to their structure is explained by using the kinetic measurements and quantum chemical calculations. All structural kinds of hydrazones are prone to autoxidation with marked differences in the rate of the reaction and have at least one hydrogen atom on nitrogen.

Laser flash photolysis and product studies have shown that 2-azido-1,3-diphenyl-propan-1-one derivatives have undergone photoinduced C-N bond cleavage, thus forming azido radicals and the corresponding benzyl radical derivatives. It is shown that solution and solid state irradiation of 3-azido-1,3-diphenyl-propan-1-one has resulted in the formation of azide radicals that abstract an H-atom to form hydrozoic acid and hence azides can be used as photoremovable protecting groups of hydrazoic acid.

The electron transfer (ET) in four symmetrically substituted naphthalene-bridged bis-hydrazine radical cations is compared within the Marcus-Hush framework. The results show that ET rates estimated for four naphthalene bridged bis-hydrazine radical cations vary significantly and show no correlation with the distance between the charge-bearing units.

Rapid reactions occur between trans-[Os(super VI)(tpy)(Cl)(sub 2)(NN(CH2)(sub 4)O)](super 2+) and a series of N- or O-bases to give the tpy-substituted Os(VI)-hydrazide complexes. The reaction occur due to the extraordinary electron withdrawing effect of Os(VI) on the tpy ligand and its ability to undergo intramolecular Os(VI) to Os(IV) electron transfer.