Abdel-Aziz S. El-Ahl

A facile and convenient synthesis of substituted tetrazole derivatives from ketones or α,β-unsaturated ketones

Abstract Triazidochlorosilane (SiCl 4 - NaN 3 in situ) is a new and efficient reagent for the direct conversion of ketones or α,β-unsaturated ketones to the corresponding tetrazole derivatives in nearly quantitative yield.

A NOVEL APPROACH FOR THE SYNTHESIS OF 5-SUBSTITUTED TETRAZOLE DERIVATIVES FROM PRIMARY AMIDES IN MILD ONE-STEP METHOD

Abstract A new mild one-step method for the conversion of primary acid amides to 5-substituted tetrazoles in nearly quantitative yields employing triazidochlorosilane (TACS) is reported.

Synthesis of triazidochlorosilane (TACS). A novel silicon mediated one pot conversion of aldehydes to nitriles

Abstract Synthesis, structure elucidation of triazidochlorosilane (TACS) and a novel conversion of aldehydes to nitriles in one pot reaction on treatment with TACS (SiCl 4 NaN 3 in Situ) reagent in acetonitrile are described.

A Convenient Regiospecific Synthesis of New Conjugated Tetrazole Derivatives via the Reaction of Dienones with the Tetrachlorosilane-Sodium Azide Reagent and their NMR Structural Assignment

Summary. Several new 1-aryl-, aralkyl-, and heteroaryl-5-(4-phenylbuta-1,3-dienyl)tetrazole derivatives and annulated tetrazole derivatives were efficiently and regiospecifically prepared in nearly quantitative yield via a facile one step reaction of dienones with a combination of tetrachlorosilane and sodium azide in acetonitrile under mild conditions. A complete structure assignment of three representative examples of the tetrazoles was achieved by advanced 2D NMR measurements including COSY, TOCSY, HSQC, HMBC, NOESY, and ROESY experiments.

A Novel Uncatalyzed Insertion Reaction of In Situ Formed Trichlorosilyl Cyanide with Imines: A Facile Silicon Mediated Synthesis of α-Aminonitriles

Abstract The tetrachlorosilane-potassium cyanide reagent combination, (trichloro-silyl cyanide-in situ) is a new, safe and versatile hydrogen cyanide substitute. The reaction of this reagent with saturated aldimines 1a–j and benzophenone oxime 3, in absences of any catalyst, affords the corresponding α-aminonitriles 2a–j and 4, respectively, in excellent yield. Under the same condition the bis-imine 5 yields the imidazo[1,2-a]quinoxaline derivative 6. Moreover, trichlorosilyl cyanide-in situ undergoes regiospecific addition onto α, β-unsaturated aldimines 7a–e to give the corresponding 1,2-addition products 8a–e, in high yield, under exceedingly mild conditions.

Novel Uncatalyzed Hydrocyanation of Ketones utlizing Tetrachlorosilane–Potassium Cyanide Reagent

Abstract A combination of tetrachlorosilane and potassium cyanide (in situ trichlorosilyl cyanide) was found to work efficiently for hydrocyanation of ketones to afford the corresponding cyanohydrins in high yield under mild conditions.

Use of reductive properties of iodotrichlorosilane II: Chemoselective reduction of α,β-unsaturated ketones and nitriles

Abstract A new synthetic procedure for the selective reduction of α,β-unsaturated ketones and nitriles, using iodotrichlorosilane (ITCS generated in situ from SiCl4-NaI) under mild conditions to produce the corresponding saturated ketone and nitrile compounds in quantitative yields, is described.

Synthesis of new pyrrolo-[3,4-c]isoxazole, pyrrolo[2,3-d]-[1,2,3]triazole, triazolo[4,5-c]-pyridazine, and dipyrrolo-[3,2-b:3′,4′-d]pyran derivatives

New pyrrolo[3,4-c]isoxazole derivatives were synthesized from the key intermediates 4-cyanopyrrolidin-3-ones in two steps. Pyrrolo[2,3-d][1,2,3]triazoles and triazolo[4,5-c]pyridazine were obtained from 2-arylhydrazono-4-cyano-1-(4′-methoxyphenyl)-3-oxopyrrolidines by refluxing with phenylhydrazine in either ethanol or glacial acetic acid. Aldol self-condensation of 1-aryl-4-cyanopyrrolidin-3-ones afforded dipyrrolo-[3,2-b:3′, 4′-d]pyran derivatives.

A new route for the synthesis of phenazine di-N-oxides

SummarySeveral phenazine 5,10-dioxides (7a–d) were prepared by the reaction of 2-methyl-3-acetylquinoxaline 1,4-dioxide (2) with different aromatic aldehydes or by direct cyclization of the quinoxaline cinnamoyl derivatives3 in basic medium. In addition, the phenazine derivatives8 and9–12 were synthesized by a one-pot reaction of substitutedo-nitroanilines with different hydroxy compounds in the presence of sodium hypochlorite solution.ZusammenfassungMehrere Phenazin-5,10-dioxide (7a–d) wurden durch Reaktion von 2-Methyl-3-acetylchinoxalin-1,4-dioxid (2) mit verschiedenen aromatischen Aldehyden oder durch direkte Cyclisierung der Chinoxalinderivate3 in basischem Milieuhergestellt. Zusätzlich wurden die Phenazinderivate8 und9–12 in einer Eintopfreaktion von substituierteno-Nitroanilinen mit verschiedenen Hydroxyverbindungen in Gegenwart von Natriumhypochloritlösung synthetisiert.

3-Pyrrolidinones: Michael Addition and Schmidt Rearrangement Reactions

Abstract Various spiro-pyrano[3,2-b]pyrrolo-2-oxoindolines 3a–d and dicyano-pyrano[3,2-b]pyrroles 5a–e have been synthesized in the present study by Michael addition of 3-pyrrolidinones 1 to isatin-3-ylidenes 2 and arylidenemalononitrile 4. Hexahydro-4-oxo-1-aryl-pyrimidine-5-carboxylic acids 7a,b were synthesized from 1 by Schmidt rearrangement.