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Cu(II), Ni(II) and Pd(II) complexes of the terdentate ligands 1-(2-pyridylmethylene)biuret and 1-(2-hydroxylphenyl)biuret (abrv. as pybiH2 and phHbiH2, respectively) have been prepared and their spectral, magnetic and voltammetric properties studied. In a square-planar coordination the metals are bonded to the pyridine N (in the pybi compounds) or to the phenolato O (in the phHbiH2 compounds) and to one or two deprotonated amide N's in [Cu(pybiH)(H2O)]+, Pd(pybiH)Cl and [Cu(phbiH)]2 respectively in Cu(pybi)(H2O) and [Ni(pybi)(OH)]− Comparison with other biuretato complexes of Cu reveals that increasing the number of coordinated amide N's goes parallel with increasing energy of the spectral dd transition and with a decrease of half wave potentials for the oxidation to Cu(III) as well as for the reduction to Cu(I) compounds. The redox orbitals seems to be located mainly on the metal centre in accord with previous MO calculations.

Among the hypotensive drugs are the N-alkyldibenz[c,e]-azepines. A representative of this class is 6-allyl-6,7-dihydro-5H-dibenz[c,e]azepine (azapetine). The present investigation involved the preparation of a new series of N-[6,7-dihydro-5H-dibenz[c,e]azepin-6-yl] acid amides namely; acetamide, benzamide, phehyl acetamide, salicylamide and p-hydroxybenzamide derivatives. Another new series of N-[6,7-dihydro-5H-dibenz[c,e]azepin-6-yl]-N-alkyl (or aryl) thioureas was prepared namely ethyl, isopropyl, butyl, cyclohexyl, benzyl, phenyl and o-tolyl thiourea derivatives. IR spectra of the two series of compounds were investigated.

Die Oximether (I) reagieren mit dem Inamin (II) zu den Carbonsaureamiden (III), die photochemisch bzw. thermisch zu den Chinolinen (IV) cyclisieren.

(1-Chloroalkyl)nitroxides 1 (Table I) are converted by tri-n-butyltin hydride into halogenfree nitroxides 3 (Table II) via intermediate nitrones 2 (reactions [6], [7]). This provides a direct method to generate non-symmetrical di-sec-alkylnitroxides 5a from chloro nitroso compounds and sec-halides by the action of tributyltin hydride (reaction [5]). Assisted by the presence of an external radical X•, (1-chloroalkyl)nitroxides 1 can lose chlorine homolytically to yield a nitrone (reaction [11]) in a process, which is reversible if the X-Cl bond is weak. The mechanism of interference of NO as an external radical is discussed in view of its essential role in the photolysis of gem-chloro-nitroso compounds which proceeds via (1-chloroalkyl)nitroxides 1. These nitroxides undergo C-Cl homolysis in most solvents; in alcoholic solvents heterolytic loss of chlorine (reactions [13]-[15]) cannot be excluded when NO is present. (1-Chloroalkyl)nitroxides 1 may also decompose thermally into a chloro nitroso compound and a chloroalkyl radical by α-cleavage of either of the two C-N bonds.

Es werden z.B. die Radikalkationen untersucht, die sich von p,p′-Bis-[ph:enyl- (triphenylphosphoranyliden)-methyl]-biphenyl bzw. seinem m,m′-Isomeren ableiten.