Reaction of isocyanides. III - synthesis of β-alkoxy imidoyl cyanides from acetals.

Tert-butyl isocyanide reacts with acetals, in presence of diethylaluminium chloride, to afford α-iminonitriles.     

Synthesis with organoboranes. 21. Synthesis of α- and gd-bamascone

Selective syntheses of α- and gd-damascone, using allylic organoboranes as the key intermediates, are described.     

Structure-Activity Relationship of Insecticidal Steroids. III. Δ4,7-6-Ketosteroids

The toxicity of steroids 1-11 for colorado beetle (Leptinotarsa decemlineata Say.) larvae was studied by contact-intestinal treatment. Active insect-growth regulators were found among the studied compounds.     

Bisindoles. 31. Synthesis of new derivatives of 2,5′- and 3,5′-bis-1H-indoles

Using p-aminoacetophenone as starting material, new derivatives of 2,5- and 3,5-bis-1H-indoles containing amino, nitro, acetyl, and ester groups have been prepared.For Communication 30, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1194–1199, September, 1993.     

Thermal Degradation of Polymers. IV. Poly-2,2′-(m-phenylene)-5,5′-bibenzimidazole

The thermal decomposition of poly-2,2′-(m-phenylene)-5,5′-bibenzimidazole has been investigated at temperatures to 916°C. Mass-spectrometric thermal analysis (MTA), supported by elemental analysis of residues at various stages of a thermogravimetric analysis, was used to determine product distribution as a function of temperature. Below 550°C, the major product is water. Above 550°C, degradation of the heterocyclic structure to hydrogen cyanide, ammonia, carbon monoxide, and water begins. Hydrogen and methane probably are formed from decomposition and condensation of the carbocyclic structure. Activation energies for the formation of each major product were derived from the MTA data. The average of these is somewhat temperature-dependent but agrees within experimental error with the value of 44 ± 11 kcal obtained from isothermal kinetics. A mechanism involving initial hydrolysis of the polymer to an amine-substituted polyamide is postulated. Subsequent homolytic reactions account for formation of the major products.     

Reaction of a chlorovinylcarbene with ketenealkyl silyl acetals. Synthesis of new α- and β-allenic carboxylates.

The reaction of ketenealkylsilylacetals with 1,1-dimethyl-2,2,3-trichlorocyclopropane in the presence of methyllithium leads to cyclopropane compounds, which, when treated with tetrabutylammonium fluoride give α- or β-allenic carboxylates.     

Synthesis and properties of thiazole halohydrazones. 2. Interaction of 2-α-chlorobenzylidenehydrazino-4-ethoxy-carbonylthiazole with nucleophiles

In the interaction of 2--clzlorobenzylidenehydrazino-4-ethoxycarbonylthiazole with nucleophiles, two competing reactions take place. 1) nucleophilic replacement of the chlorine atom to form the corresponding substitution product; 2) elimination of a hydrogen chloride molecule, concluding in cyclization of the intermediate nitrilimine to form 3 phenyl-5-ethoxycarbonylthiazolo(2, 3-c]-1, 2, 4-triazole. The direction taken by the interaction depends on the nature of the nucleophile and is determined primarily by the ratio of basicity and nucleophilicity of the agent.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, 256–259, February, 1994. Original article submitted December 30, 1993.     

Polymorphism of Inclusion Complexes and Unsolvated Hosts. IV. Dimorphism of the Acetone Host–Guest Complex of Dianilinegossypol. Structures of the α- and β-Phase Complexes

Crystal structures of the - and -phase inclusion complexes of dianilinegossypol with acetone obtained at 20° and 30 °C, respectively, have been determined by X-ray structure analysis. Crystal data of the -phase complex are: C₄₂H₄₀O₆N₂2C₃H₆O, orthorhombic, space group Pccn, a = 29.501(9), b = 10.866(2), c = 13.756(3) Å, V = 4409(1) ų, Z = 4, D _x = 1.18 g cm^-3. The structure has been refined to a final R value of 0.117 for 1401 observed reflections. The host–guest ratio for the -phase complex is the same (1 : 2) and the crystals are monoclinic, space group C2/c, a = 28.352(6), b = 11.836(2), c = 13.196(1) Å, = 93.05(1)°, V = 4422(2) Å3, Z = 4, D _x =1.18 g cm^-3. The structure has been refined to a final R value of 0.077 for 1414 observed reflections.In both phases molecules of dianilinegossypol form hydrogen-bondedribbons by O(4)–-HO(3) H-bonds. Phases are determined by the same structural motif. In the -phase complex the cages are in the form of prisms but in the -phase clathrate they undergo a modification by shrinking in two directions and widening in one. Molecules of acetone are hydrogen bonded to the host molecules via aO(1)–-HO(G) bond and are accommodated in cavities for both complexes, i.e. both phases are cryptate-type inclusion complexes.Supplementary data relevant to this publicationhave been deposited with the British Library,No. SUP 82227 (24 pages).     

Aromatic annelation. A synthesis of (±)-3-methyl-8,14-dehydromorphinan.

(±)-3-Methyl-8,14-dehydromorphinan has been prepared by forming the aromatic ring in the late stages of the synthesis.     

X-ray structural investigation of gossypol and its derivatives. XXVII. Structure of the condensation product of gossypol and (−)-α-phenyletiiylamine

The structure of the product of condensation of gossypol with (–)--phenylethylamine has been determined. It has been shown that a possible cause of the difficulty in separating racemic gossypol into optically active components is not a racemization of (–)--phenylethylamine on its condensation with gossypol but the high tendency of gossypol and its derivatives to form dimers.Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 676–681, September–October, 1995. Original article submitted February 6, 1995.     

Investigations of 2,3′-biquinolyl. 7. Thiolation of 1-alkyl-3-(2-quinolyl)quinolinium halides

Thiolation of 1-alkyl-3-(2-quinolyl)quinolinium halides by a mixture of sulfur with KOH in DMF leads to formation of 1-alkyl-1,4-dihydro-2,3-biquinolyl-4-thiones, rearrangement of which in boiling ethylene glycol makes it possible to obtain 4-alkylthio-2,3-biquinolyls.     

2-Benzopyrylium salts. 41. Intramolecular transformations of 4-1′-dimers of α-unsubstituted 2-benzopyrylium salts

Recyclization reactions of 4-1-dimers of 2-benzopyrylium salts leading to naphthalene derivatives are described. A new variant of the intramolecular Cannizzaro rearrangement has been discovered.For communication 40, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 175–180, February, 1991.     

Asymmetric synthesis of heteroorganic analogs of natural products. 6. (S)-α-amino-ω-phosphonocarboxylic acids

Alkylation, by -haloalkylphosphonates, of the Ni(II) complex of the Schiff base formed from glycine and (S)-2-N-(N¹-benzylprolyl)-o-aminobenzophenone has been used for the asymmetric synthesis of (S)-2-amino-4-phosphonobutyric and (S)-2-amino-5-phosphonovaleric acids.Institute of Bioorganic Chemistry and Oil Chemistry, Ukrainian Academy of Sciences, 250800 Kiev. A. N. Nesmeyanov Institute of Organometallic Compounds, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 2, pp. 397–402, February, 1992.     

The heterometric micro-analysis of cobalt with α-nitroso - β-naphthol. a general study.

1. The reaction between cobaltous or cobaltic and α-nitroso-β-naphthol was extensively studied heterometrically both in water and in alcoholic solutions. The influence of complexing agents and of the acidity on the precipitation of cobalt-α-nitroso-β-naphthol was investigated. In all cases the molar ratios : [Co] [αβ] at the end of the precipitation were established and the possible compounds which were obtained were discussed. 2. Micro-analytical heterometric methods are given for the determination of cobalt or α-nitroso-β-naphthol. The determination can be carried out with precision even in concentrations as low as 0.0001M Co. Conversely, very dilute alcoholic solutions of α-nitroso-β-naphthol may be titrated with precision with a dilute solution of cobalt nitrate. 0.2–0.5 mg cobalt in 20 ml solution are required for the analysis. The error lies between zero and 3%.