Stereochemical transformations of some seven-membered pyridoxine dimethyl ketals

According to the data of single crystal X-ray diffraction analysis and computational methods, the seven-membered rings of acylated pyridoxine acetonides have C ₂ symmetry. Two stereochemical transformations in solutions, enantiotopomerization of P-, M-conformations with spiral chirality of twist-boat forms and diastereotopomerization of structures that differ in the configuration of the phenolic oxygen substituents, were revealed by dynamic ¹H NMR spectroscopy.     

Synthesis and some transformations of thiophene series sulfides

The compound of formula C₁₀H₇N8₄, formed by the reaction of sodium-2-diethoxymethyl-3-thienylmercaptide with ammonia followed by acidification to pH 8 [1], is evidently bis(3-thiono-2-thienylidene)-dimethylamine (Ia). The action of primary amines on the thienylidenamine Ia gives N-substituted 3-mercapto-2-thienylidenimines (XIIa-c). With nickel acetate the azomethine XIIa forms an intramolecular complex (XIII).For Part XII see [1].     

Synthesis and some transformations of functionally substituted lactones

Reactions of functionally substituted unsaturated five- and six-membered cyanolactones with α- and β-hydroxy ketones in the presence of sulfuric acid gave substituted 2-oxofuran- and 2-oxopyran-3-carboxamides. Hydrolysis of some keto amides thus obtained afforded the corresponding carboxylic acids, and reactions with hydrazines and semicarbazides led to hydrazones and semicarbazones at the side-chain oxo group.     

Synthesis and some transformations of polybrominated quinone diazides

The reduction of polybrominated o- and p-nitrophenols with granular tin in concentrated aqueous HCl gave polybrominated aminophenols which were diazotized with sodium nitrite in concentrated sulfuric acid at 0°C to obtain polybrominated o- and p-quinone diazides. Their thermolysis with elimination of nitrogen generated ketocarbenes which reacted with acetylacetone to form insertion products at the activated methylene group. Ketocarbenes generated from o-quinone diazides reacted with typical dipolarophiles such as acetonitrile, benzonitrile, styrene, and phenylacetylene to afford the corresponding [3 + 2]-cycloaddition products.     

Reaction of acetylferrocene with dimethylformamide dimethyl acetal and some transformations of the reaction product

1-Dimethylamino-3-ferrocenyl-3-oxoprop-1-ene was synthesized by the reaction of acetylferrocene with dimethylformamide dimethyl acetal. Its reactivity in the reactions with mononucleophilic (sodium salts of phenol, thiophenol, benzenesulfinate, diethylphosphorous acid) and binucleophilic reagents (hydrazine hydrate, hydroxylamine, amidines, 1,2-diaminobenzene, 2-aminophenol, 2-aminothiophenol) and methyl iodide was studied. As a result, we obtained new ferrocene-containing α-keto-unsaturated compounds and heterocycles of pyrazole, isoxazole, pyrimidine, and benzazepine series. In the reaction with CH₃I formed ferrocenoylacetylene which in the presence of dicarbonyl-bis(triphenylphosphine)nickel catalyst easily trimerized to give a mixture of 1,2,4- and 1,3,5-triferrocenoylbenzene.     

Synthesis and some transformations of thioesters of thienylacrylic acid

A number of thioesters of thienylacrylic acid were obtained by the condensation of 2-formylthiophene and 5-bromo-2-formylthiophene with acetylenic thioethers in the presence of boron trifluoride etherate. The reaction of the condensation products with hydrazine hydrate is accompanied by intramolecular cyclization to form the corresponding pyrazolines. The IR spectra of the synthesized compounds are discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1348–1349, October, 1971.     

Synthesis and some transformations of 2-acylmethyl-1,3-oxathiolanes

2-Acylmethyl-1,3-oxathiolanes, which form oximes with hydroxylamine and perchlorates with perchloric acid, were synthesized by reaction of -alkynyl ketones with ß-mercaptoethanol.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1041–1043, August, 1978.     

Synthesis and some transformations of 2-alkenyl-4-alkoxymethylbutanolides

The alkylation of 4-alkoxymethyl-2-ethoxycarbonylbutanolides led to the formation of 2-alkenyl-4-alkoxymethyl-2-ethoxycarbonylbutanolides which at alkaline hydrolysis provided new 2-alkenyl-4-alkoxymethylbutanolides. By oxidation of the latter with a mixture of hydrogen peroxide and formic acid 4-alkoxymethyl-2-(2-R-2,3-dihydroxy)propylbutanolides were obtained. The diololactones were shown to suffer under the conditions of the pinacol-pinacolone rearrangement a conversion into previously unknown formyl-and epoxylactones.     

Synthesis and some transformations of 2,6-diphenyl-4-hydroxybenzofuran

A 4-oxotetrahydrobenzofuran derivative was obtained from 5-phenylcyclohexane-1,3-dione and phenacyl bromide, and dehydrogenation of the latter gave 2,6-diphenyl-4-hydroxybenzofuran. Some reactions of 2,6-diphenyl-4-hydroxybenzofuran and its derivatives were studied.     

2-perfluoroalkanoylcyclopentane-1,3-diones. Synthesis and some transformations

2-Perfluoroalkanoylcyclopentane-1,3-diones were synthesized for the first time by acylation of cyclopentane-1,3-dione with perfluorocarboxylic acids in the presence of 1,1??-carbonyldiimidazole or with perfluorocarboxylic anhydrides in the presence of imidazole. 2-Perfluoroalkanoylcyclopentane-1,3-diones were selectively reduced to 2-(1-hydroxyperfluoroalkyl)cyclopentane-1,3-diones by the action of triethylsilane in trifluoroacetic acid in the presence of a catalytic amount of lithium perchlorate. Treatment of the title compounds with oxalyl chloride and subsequent reaction with 2 equiv of primary amine (4-fluoroaniline, 4-fluorobenzylamine, 3,4-difluoroaniline, 3-trifluoromethylbenzylamine) gave the corresponding 3-arylamino-2-perfluoroalkanoylcyclopent-2-en-1-ones.     

Synthesis and some transformations of sulfides of the thiophene series

Some 2-substituted 4-keto-2,3-dihydrothieno[3,2-e]-1,3-thiazines were obtained by condensation of 2-mercapto-5-ethylthiophene-3-carboxamide with aldehydes and ketones in the presence of gaseous HCl.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 909–910, July, 1972.     

Synthesis and some chemical transformations of 3-ferrocenyl-3-phenylcyclopropene

Crystalline 3-ferrocenyl-3-phenylcyclopropene was obtained by dehydrobromination of 2-bromo-l-ferrocenyl-l-phenylcyclopropane with potassiumtert-butoxide in dimethyl sulfoxide. The compound synthesized undergoes catalytic hydrogenation to l-ferrocenyl-I-phenylcyclopropane, reacts with 1,3-diphenylisobenzofuran to give the expected product of stereospecific [4+2[-cycloaddition and 3-ferrocenylindene, and also undegoes opening of the small ring on treatment with superacids to give 3-ferrocenylindene as the major product. The data of single crystal X-ray diffraction analysis of 1-ferrocenyl-l-phenylcyclopropane and the diene adduct of 3-ferrocenyl-3-phenylcyclopropene with 1,3-diphenylisobenzofuran are given.     

Synthesis and transformations of some new 2,4-bismethylene-1,3-ditelluretanes

A novel four-membered 1,3-ditelluretane dialdehyde 8/9 was synthesized from trimethylsilylethynyl tellurolate. The dialdehyde was transformed into extended tetrathiafulvalenes (14 and 15). These are the first examples of ditelluretane spaced TTF derivatives.     

Synthesis and some transformations of pyrroles with aliphatic acyl substituents

A number of higher aliphatic pyrryl ketones were synthesized. It is shown that a carbethoxy group in the 5 position of the pyrrole ring relatively weakly deactivates the 3 position of the ring to electrophilic attack during Friedel—Crafts acylation but hinders this reaction considerably when it is in the adjacent 4 position. The oxidation of the -methyl group in a series of pyrryl ketones and the corresponding alcohols was studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 27–30, January, 1973.