A Convenient Synthesis of Aminomethylphosphonic Acid

A novel procedure for the preparation of aminometnylphosphonic acid (AMPA) is described. This compound. which has been shown to have some biological activity, is synthesized by treating N-hydroxymethylbenzamide with a mixture of phosphorous trichloride and trimethyl phosphite, followed by hydrolysis of the ester intermediate.     

Convenient Synthesis of Dicyclohexyldithiophosphinic Acid

Dicyclohexyldithiophosphinic acid was synthesized by a three-step strategy through the Grignard reaction of PSCl₃ with cyclo-C₆H₁₁MgBr and the P-P bond-cleavage reaction of the intermediate. The ¹H NMR data of ammonium dicyclohexyldithiophosphinate 4 and dicyclohexyldithiophosphinic acid 5 were characterized by ¹H-¹H correlation spectra.     

A Convenient Procedure for the Synthesis of Ursodeoxycholic Acid Sulfated Derivatives

The mono- and bis(sulfooxy) derivatives of ursodeoxy-cholic acid are, contrary to a previous report, easily prepared by a very simple direct sulfation procedure.     

A Convenient Synthesis of Novel Meldrum＇s Acid C60 Fullerene Derivatives

A series of novel Meldrum＇s acid C60 derivatives were prepared in moderate yields from a convenient one-pot reaction of C60, the Meldrum＇s acid derivatives, 12 and 1,8-diazabicyclo-[5,4,0]-undec-7-ene （DBU） in toluene at room temperature under nitrogen atmosphere. All the new compounds were fully characterized by the spectral data and elemental analysis. A carbene intermediate mechanism was proposed for this reaction.     

A Convenient Synthesis of 3,5-bis(Trifluoromethyl)Salicylic Acid

A convenient method is reported for the synthesis of the biologically important intermediate, 3,5-bis(trifluoromethyl)-salicylic acid, by a sequence involving diazotization/iodination of 2-bromo-3,5-bis(trifluoromethyl)aniline, displacement of the bromide with sodium methoxide, and carboxylation of the anion generated by lithium-iodine exchange with carbon dioxide. Alternatively, the anion could be carbonylated with dimethylformamide and the resulting aldehyde oxidized with Jones reagent. Demethylation of 3,5-bis(trifluoromethyl)anisic acid with boron tribromide gave the title compound.     

A Convenient One-Pot Synthesis and Nematicidal Activity of Nicotinic Acid Amides

Russian Journal of Organic Chemistry - Seven nicotinic acid amides were synthesized by condensation of nicotinic acid adsorbed on silica gel with different aromatic amines. The synthesized...     

Selective Bromination of Ketones. A Convenient Synthesis of 5-Aminolevulinic Acid

Bromination of unsymmetrical ketones with Br₂ in methanol proceeded regioselectively in good yield at the less substituted methyl carbon. The bromination of levulinic acid using this method was followed by azidation and amination to lead to an efficient three-step synthesis of 5-aminolevulinic acid in 36% overall yield.     

A Convenient Modification of the Fischer Indole Synthesis with a Solid Acid

A new one-pot version of the titled reaction involves heating a mixture of a carbonyl compound, a phenylhydrazine, and the cation exchange resin Amberlite IR 120 in refluxing ethanol. A variety of enolizable aldehydes, and ketones and several substituted phenylhydrazines could thus be converted to the corresponding indoles in excellent yields (70–88%). Reaction times were typically 6–10 h, with the resin being then filtered off and the product isolated after minimal workup.     

A Convenient Synthesis of O-Alkyl-S-allenyl-Phosphoramidates

Ten title compounds 2a-j were synthesized by utilising mercuric (I) catalyzed thiono-thiolo rearrangement of O-propargyl-O-alkyl-pho-sphoramidothionates (1a-j) in HAc-NaAc buffer (PH=3.6). The yield of compounds 2a-e and 2f-j is 58–67% and 12–41%. This is the example of [3,3]-sigmatropic type rearrangement of 1,5-enyne system in thionop hosphoramidate chemistry.     

A Convenient Synthesis of Sendaverine

Sendaverine was isolated from Corydalis aurea willd by Manske and it was found to possess a tetrahydro-isoquinoline skeleton¹. The structural formula of the alkaloid has been established by the unambiguous synthesis by Kametani² and Miwako Mori et al.³     

A Convenient Synthesis of Tryptamines

Reaction of tosylmethyl isocyanide with substituted formyl indoles gave the nitrile with one more carbon atom. Hydrogenation of this nitrile afforded the corresponding tryptamine.     

A Convenient Synthesis of Thioimidates

Thioimidates are useful reagents in preparative organic chemistry: for example, they are key intermediates for the synthesis of β-lactams bearing a thioether function at position 4, via an “acid chlorideimine” type reaction.¹     

A Convenient Synthesis of Protoanemonin

Abstract

A new convenient synthesis of protoanemonin (1) starting from 2-deoxy-d-ribose (3) is described. A key step in the sequence is the successive β- and δ-eliminations of 3,5-di-O-p-toluoyl-2-deoxy-d-ribono-1,4-lactone (6).     

A Convenient Synthesis of Triquinacene

We have recently reported the synthesis of a derivative of triquinacene (2,3-dihydrotriquinacen-2-one (14)⁴) from Thiele's acid (1). Although this new synthetic route is simple in concept, it suffers from a large number of chemical steps. We wish to communicate an important overall simplification of this synthetic scheme which makes readily available triquinacene (22) and several of its derivatives.     

Convenient Synthesis and Isolation of Conformationally Rigid Glutamic Acid Analogues

Abstract

A convenient synthetic methodology for the synthesis of highly conformationally restricted tricyclic aminodicarboxylic acids bridged analogues of glutamic acid, is presented. The process can be used for preparation of the novel glutamate analogues.     

Convenient Synthesis of 2, 5-Dimethyl-2-Furoic Acid

A synthesis of 4, 5-dimethyl-2-furoic acid amenable to large scale is reported affording the titled compound in 25% yield.     

A Convenient One-Step Gingerol Synthesis

Racemic 6-gingerol can be obtained in a one-pot reaction by hexanal addition to the dianion of zingerone at low temperature. Similarly, addition of octanal or decanal to the dianion provides 8-gingerol or 10-gingerol, respectively. Acid treatment of the gingerols allows for formation of the corresponding shogaols.     

A Convenient Synthesis of the Monodimethylacetal of Fumaraldehydic Acid and the Corresponding Chiral Esters

A short synthesis of the monodimethylacetal of fumaraldehydic acid 3 and the corresponding chiral esters 4 and 5 is reported. The key step is the oxidation of the fumaraldehyde monodimethylacetal 2.