Reagents ammonium formate

Reduction ofimines using formates Ammonium formates and formic acid have been employed as reducing agents in the synthesis of secondary amines from imines. By simple mixing of the reagents and microwave irradiation without solvent, the amines were produced in good yields within 2.5-10 min (Scheme 4.28)51. 

Durst and Sharma [86] have reported the stereospecific synthesis of 3-spiro-epoxyazetidin-2-ones 55 (Scheme 14). The oxidation of the diastereoisomers of compound 52 with PCC provided a single acetyl compound 3-acetyl-3-benzyloxy-azetidin-2-one 53. Nonchelation controlled L-Selectride reduction of 53 gave the isomerically pure 3-hydroxyethylazetidin-2-one as the sole reduced product, which was further converted to tosylate 54 using NaH/tosylimidazole. The debenzylation-oxirane formation sequence was conveniently performed as a single pot operation with ammonium formate, 5% Pd/C in refluxing methanol as the hydrogen transfer reagent combination. 

Use of ammonium formate as a catalytic hydrogen-transfer reagent has been reviewed.2... 

Gradients of aqueous and organic mobile phases are typically used for LC-MS/MS analysis of drug compounds and metabolites. The most common aqueous solvents are water with 0.1 % formic acid or 0.1 % acetic acid (v/v) or volatile buffers like 5 mM ammonium-acetate or ammonium-formate. Often adjusted to a certain pH value with the corresponding acid or base (the pH of the eluents will have to be optimized with respect to the polarity of the analytes, since ionic species will have very low or no retention on the reversed pahse LC-columns). Other volatile buffers can be used as well. Phosphate buffers should be avoided, since they will cause suppression of the ionization and thus lead to very bad analytical performance (Venn 2000). Reagents like triethyl-amine should also be avoided as mobile phase or as part of mobile phases. They induce ion suppression as well. In terms of the organic solvents, methanol and acetonitrile are very widely used and they are very well suitable for LC-MS. Other solvents can be used as well, as long as they are compatible with the materials used in the LC-MS system. 

Hyperforin (containing traces of adhyperforin) was obtained form Dr. W. Schwabe Pharmaceuticals (Karlsruhe, Germany). Methanol and acetonitrile were purchased from Caledon (Georgetown, ON, Canada) in HPLC-grade quality. Purified water from a Milli-Q water purification system (Millipore, Bedford, MA) was used. All other solvents and reagents (Tris buffer, ascorbic acid, formic acid and ammonium formate) were obtained from Sigma-Aldrich (Missisauga, ON, Canada). 

This reagent silylates hydroxy groups, but the resulting ethers are generally hydrolyzed readily when the peptide is dissolved in H2O. If a TMS ether is stable, MS of the product will show a contaminant 70 amu higher than the theoretical peptide mass. Such ethers can be cleaved by treatment with a solution of ammonium formate in MeOH/H20 (l l).t °l... 

Ammonium formate hydrogenolysis of 7t-allyl-palladium(II) complexes formed via oxidative addition of Pd(0) to propargylic carbonate esters is a useful method for preparing disubstituted alkynes, as depicted below. This method of deoxygenation avoids the use of expensive and toxic reagents often associated with the free-radical Barton-McCombie deoxygenation. °... 

Condensation of 3-acylamino-2-acylthiophenes 92 (R = COR) with ammonium formate gave the corresponding thienopyrimidines 93 (R, R = H or Me) [74CR(C)1513 76BSF151]. The substituted methyl derivatives of 93 (R = XCH2) were prepared by the action of nucleophilic reagents on l,2,3-triazolo[3,4-a]thieno[3,2-d]pyrimidines 94 (80JHC1771). 

Scheme 3 Reagents, (a) Allyl bromide/Acetone followed by optical resolution (b) Benzyl chloroformate, NaHC03 (aq), CHC13(98%) (c) Pd/C, H20, AcOH (100%) (d) di-tert-butyl dicarbonate, CH2C12 (98%) (e) Pd/C, Ammonium formate, MeOH (97%) (f) Allyl bromide, K2CQ3, Acetone (98%) (g) TFA, Triethylsilane, CH2C12(89%) (h) Pd/C, H2Q, AcOH [60]...

The Leuckart-Wallach procedure is not very suitable for use with lower aliphatic ketones. However, acetophenone and similar higher-boiling ketones afford the primary amines in 70-80% yield when treated with the mixture of ammonium formate and formamide (the Ingersoll reagent) that is formed when ammonium formate or an ammonium carbonate-carbamate mixture is heated with formic acid at 165°.1022... 

Several modifications of this reduction involve formates and are effective for reduction of various functional groups. A mixture of formic acid and ethyl magnesium bromide was used to reduce decanal to decanol in 70% yield. Decanal was also reduced to decanol in 69% yield by using sodium formate in N-methyl-2-pyrrolidinone as a solvent. Functional groups other than carbonyl derivatives can be reduced under relatively mild conditions with formate derivatives. Ammonium formate, in the presence of palladium on carhon was used to reduce an azide to a primary amine.Aliphatic nitro compounds are also converted to an amine with this reagent. l°... 

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