V. A. Usov

Thioformyl Compounds. Synthesis, Structure and Properties

Abstract Available data concerning the synthesis of thioformyl compounds such as thioaldehydes, O-alkyl thio-formates, alkyl dithioformates, thioformamides, thioformyl halides and thioformylphosphine oxides, have been summarized and systematized in the present review. The importance of thioformyl compounds as intermediates, synthons and reagents in fine organic synthesis is discussed.

β-Heterosubstituted α,β-Unsaturated Thioketones. Some Problems of Synthesis and Structure

Abstract A review of synthetic routes to aliphatic, alicyclic, and heterocyclic thioketones having an X—C[dbnd]C—C[dbnd]S group (X = NR1R2, OR, SH, SR, CI, CN) is given. Enamino thioketones have been most thoroughly studied synthetically. The preparation of these compounds involves processes of building up of the thioketone group, on one hand, and insertion of the amino function into sulfur organic compounds, on the other hand. The synthesis of β-alkoxy, β-alkylthio and β-chloro substituted vinylene thioketones is based on sulfhydrolysis of immonium salts of the type at the bond as described in papers from the latest three years. The sulfhydrolysis ofβ-alkoxy (or alkylthio) vinylene thioketones has provided a convenient synthetic approach to some β-mercaptovinylene thioketones (β-di-thiodiketones). The synthesis of the first β-cyanovinylene thioketone stabilized as a trimer is described involving the cyanolysis of β-alkoxy and β-chlorovinylene thioketone. The main synthetic routes to enamino thiocarboxami...

Mesomerically stabilized thioaldehydes. 3-Thioformylindole and its alkyl and phenyl derivatives

Abstract3-Thioformylindole and its previously unknown 2-methyl-, 2 -phenyl-, and 1-ethyl substituted derivatives have been synthesized by the thiolysis of the corresponding indolylmethylenimmonium perchlorates. The thioaldehydes containing no substitutdt at the nitrogen atom were isolated as crystalline solvates with DMSO and DMF. Monitoring of 3-thioformylindole formation was effected by polarography and spectrophotometry.

PMR spectral study of the protonation of N,N-disubstituted 3-amino-2-aryl-1-indenones

Conclusions1.N,N-disubstituted 3-amino-2-aryl-1-indenones are protonated by perchloric and trichloroacetic acids in deuteroacetone at C2 with the formation of the corresponding 3-oxo-2-aryl-1-indaniminium salts.2.An increase in the barrier to the hindered internal rotation about the C-N bond in N,N-disubstituted 3-amino-2-aryl-l-indenones is observed with a decrease in the extent of the C2-protonation of these compounds.

Quantum-chemical study of the structure and prototropic conversions of 2-methyl-1,3-bishetero derivatives of indene and indan

ConclusionsThe optimal conformations of the prototropic forms of 2-methyl-1,3-bishetero derivatives of indene and indan have been calculated by the CNDO/BW method, and the optimal paths for intramolecular proton transfer have been determined. The dependence of the heights of the barriers to intramolecular prototropic transitions on the character of the heteroatoms has been established.

Investigation of prototropy in the thio analogs of 2-acetyl-1,3-indanedione by the CNDO/BW method

Conclusions1.The optimum conformations of the prototropic forms of the thio analogs of 2-acetyl-1,3-indanedione were calculated by the CNDO/BW method, and the optimum paths for intramolecular transfer of the hydrogen atom were determined.2.Internal prototropy is a fast process on the NMR time scale, while external prototropy is slow.3.In an acidic medium intermolecular proton transfer can be fully competitive with the intramolecular process.

Cleavage of substituted dispiro [bis(3′-aminoindene)-1′, 4;1′,5-(1,3-dithiolanes)] by means of transition metal salts

Dispiro[bis(3-aminoindene)-1′,4;1′,5-(1,3-dithiolanes)] react readily with Cu+, Ag+, Hg+, and Hg2+ salts to give the corresponding bis(1-imino-3-indenyls) and methanedithiol derivatives. Bis(1-oxo-3-indenyls) are formed when the reaction is carried out in the presence of water. The reactivities of the 1,3-dithiolanes were examined with allowance for electronic and steric factors, and the reactivities of the metal cations were examined from the point of view of Pearsons theory. Methods for the alternative synthesis of the compounds obtained were found, and their IR and PMR spectra are discussed.

Barrier of rotation around N-C=bond in N,N-disubstituted 3-amino-2-arylinden-1-ones and 3-amino-2-arylindene-1-thiones

1. The activation parameters of hindered rotation around the N-C= bond in 3-N,N-dimethylamino-2-(4′-methoxyphenyl) indene-1-thione, 3-piperidino-2-phenylindene-1-thione, 3-piperidino-2-(4′-methoxyphenyl)indene-1-thione, and their oxygen analogs were determined. The barriers of rotation decrease somewhat when the dimethylamino group is replaced by the piperidino group. 2. The insertion of a OCH3 group in the p position of the 2-phenyl ring of the studied compounds has practically no effect on the ΔG≠ value of rotation around the N-C= bond. 3. The value of the barrier of inversion of the N atom and (or) conversion of the 3-piperidine ring was estimated for the 3-piperidino-2-phenylindene-1-ketone.

Formation of spiro-substituted 1,3-dithiolanes and thiiranes in the reaction of 3-aminoindene-1-thiones with aliphatic diazo compounds

Abstract3-Aminoindene-1-thiones react readily with diazomethane to give the corresponding 4,4;5,5-dispiro-substituted 1,3-dithiolanes. The production of both 2,2-spiro-substituted thiiranes and products of desulfuration of the latter is possible in the reaction of 3-aminoindene-1-thiones with substituted diazomethanes. The thermolysis, hydrolysis, and salt-forming reactions of the compounds obtained were investigated.

Protonation of some cyclic β-Aminovinylthiones and β-aminovinylketones

The NMR method was used to study the protonation of 3-N,N-dimethylammo-5,5-dimethyl-3-cyclohexene-1-thione, 3-N,N-dimethylamino-2-phenylidene-1-thione, and their oxygen analogs. The protonation center for these compounds is different, and is, respectively, N and O, and S and 2-C.