Reaction of α-keto hydrazonyl bromide with carbanions of some active methylene compounds

Treatment of 1-phenyl-2-bromo-2-arylhydrazonoethanone (VII) with sodium etiolates of 2,4-pentanedione, 1-phenyl-1,3-butanedione, dibenzoylmethane, ethyl benzoylacetate, acetoaceta-nilide, and of benzoylacetanilide in ethanol afforded the substituted pyrazoles, VIII-XIII, respectively. The results show that VII, unlike 1-phenyl-2-bromo-2-hydroximinoethanone (V), is not easily deprotonated by carbanions; and that its reactions with β-diketones, β-keto esters, and β-keto amides follow one and the same mechanism. The structures of the products (VIII-XIII) were inferred from their elemental analyses and spectral data.     

Reaction of 1-alkylthioisoquinolinium salts with active methylene compounds

2-Alkyl-1-alkylthioisoquinolinium salts were readily prepared from 2-alkyl-1(2H)-isoquinolones via 2-alkyl1(2H)-thioisoquinolones in two steps. Under mild conditions, the reaction of 2-alkyl-1-alkylthioisoquinolinium salts with active methylene compounds in the presence of sodium hydride afforded 2-alkyl-1-(substituted methylene)iso-quinolines in good yields. Pyrrolo[2,1-a]isoquinolines were synthesized by the cyclization of 2-benzyl-1-(substituted methylene)isoquinolines using acetic anhydride.     

3,3,3-Trifluoropropan-1-OL and 3,3,3-trifluoropropanal

Acetoxymercuration of 3,3,3-trifluoropropene leads to 1-acetoxy-3,3,3- trifluoropropene which is hydrolysed to 3,3,3-trifluoropropanol, oxidation of which affords 3,3,3-trifluoropropanal.     

Reaction of dicymantrenylketone with mesitylmagnesium bromide

The reaction of dicymantrenyl ketone with the Grignard reagent 2,4,6-Me₃C₆H₂MgBr in THF occurs as the insertion of the mesityl substituent in the -position of one of the cyclopentadienyl rings to give (2-mesitylcymantrenyl) cymantrenyl ketone (4), rather than as addition at the C=O group. Reduction of4 by NaBH₄ in a THF-EtOH mixture affords (2-mesitylcymantrenyl)cymantrenylmethanol (5). Ionic hydrogenation of5 with the HSiEt₃/CF₃COOH system gives (2-mesitylcymantrenyl)cymantrenylmethane (7). The structure of alcohol5 has been established by X-ray diffraction analysis.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 723–728, April, 1994.     

Alkylation of tertiary arsines with methylene bromide and subsequent anion exchange

Tertiary arsines react with methylene bromide to give (bromomethyl)trialkyl(aryl)arsonium bromides. Treatment of the latter with magnesium perchlorate in aqueous ethanol solutions leads to anion exchange forming the corresponding tertiary arsonium perchlorates in nearly quantitative yields.     

Reaction of tetrachloropyrazine with active methylene compounds

When tetrachloropyrazine was allowed to react with the anions formed from diethyl malonate and malonitrile, the normal alkylation took place. When the anions from ethyl acetoacetate and N,N-diethylacetoacetamide were used, alkylation was followed by enolization and ring formation to give furo [2,3-b] pyrazines. The structure proof and reaction of the furo [2,3-b] pyrazines are discussed.     

Reaction of acetyl bromide with triphenylarsine oxide

Conclusions Triphenylarsine dibromide and acetic anhydride are formed when acetyl bromide and triphenylarsine oxide, taken in a 21 molar ratio, are reacted in anhydrous toluene.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 168–169, January, 1971.     

Reaction rate of ethylmagnesium bromide with thiobenzophenone

Conclusions The reaction rate of ethylmagnesium bromide with thiobenzophenone was studied. The obtained data indicate that the monomeric Grignard reagent takes part in the reaction when its concentration is below 0.2 mole/liter, and the corresponding dimer at higher concentrations [13].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2394–2396, October, 1981.     

Reaction of thiopyrylium ion with active methylene compounds

The reaction of 2,4,6-triphenylthiopyrylium ion with several active methylene compounds in the presence of base has been found to yield 2,4,6-triphenylbenzene derivatives. In the case of the reaction of 2,4,6-triphenylthiopyrylium fluoroborate with nitromethane, an alkali treatment gave 2,4,6-triphenylnitrobenzene, and an acid treatment afforded 2,4,6-triphenylbenzene, respectively. From these results, the reaction behaviour of the thiopyrylium ion has been discussed.     

Reaction of zero-valent cobalt and nickel with ethyl bromide

Conclusions A study was made of the composition of the gaseous products that are formed when zero-valent Co and Ni, complexed with C₂H₅MgBr, are reacted with C₂H₅Br, and it was shown that the latter is decomposed quantitatively to give ethane and ethylene in an equimolar ratio, and a certain amount of butane. The formation of the reaction products is not related to the development of free radical steps in solution.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1170–1172, May, 1973.     

Reaction of 3-azidoisoxazoles with active methylene compounds

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Reaction of allyl bromide with carbonyl compounds mediated by tributylbismuthine [1]

In the presence of tributylbismuthine, allyl bromide was found to react with either aldehydes or ketones to give the corresponding homoallylic alcohols and their allylic ethers in good total yields.     

Reaction of 2,3,4,5,6-pentabromobenzyl bromide with 2,4,6-triphenylpyranyl

The main process in the reaction of 2,4,6-triphenylpyranyl with 2,3,4,5,6-pentabromobenzyl bromide in 2-propanol is electron transfer to give 2,4,6-triphenylpyrylium bromide and 2,3,4,5,6-pentabromobenzyl radical.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 9, 2004, pp. 1510–1512.Original Russian Text Copyright © 2004 by Burtasov, Mishunyaeva, Pryanichnikova, Shishkin, Tanaseichuk.This revised version was published online in April 2005 with a corrected cover date.     

Reaction of tertiary cyanoacetylenic alcohols with hydrogen bromide

Conclusions The addition of HBr to tertiary cyanoacetylenic alcohols is accompanied by intramolecular cyclization, which leads to the hydrobromides of bromiminodihydrofurans.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1646–1647, July, 1983.