A New Synthesis of α-Aryltelluro Esters

Aryltellurenyl iodides react with Reformatsky reagents in dry THF at room temperature rapidly to produce α-aryltelluro esters in good yields.     

A Convenient Synthesis of Esters of β-Phenylglutamic Acid Under Aqueous Conditions

Abstract

Several esters of β-phenylglutamic acid (3, 4) are prepared by Michael reaction of glycine ester Schiff bases 1 and 2 under aqueous conditions.     

A Convenient Method for the Synthesis of α-Functionalized Chlorophosphonic Esters

α-Functionalized chlorophosphonic monoesters were easily prepared by a selective chlorination of the corresponding phosphonic diesters with phosphorus oxychloride.     

A New Convenient Synthesis of Pyridine-N-oxides

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A Convenient Synthesis of β-Amino Acid

We have reported the reductive cleavage of azlactones¹ and phenylhydrazones² of carbonyl compounds in the presence of a suitable catalyst. In this paper a general method involving a one step synthesis of β-amino acid^3,4, in good yield, through catalytic reduction of oximes of α-β-unsaturated acid is reported. This method involves the reaction of α, β-unsaturated acid with hydroxylamine hydrochloride in the presence of sodium acetate. Markovnikov's rule is followed in the synthesis of oximes of α, β-unsaturated acids.     

Convenient Synthesis of Vinyldiazomethanes from α-Diazo-β-Keto Esters and Related Systems

A series of vinydiazomethanes were readily prepared by sodium borohydride reduction of a-diazo-p-ketoesters followed by phosphorus oxychloride induced dehydration of the resulting a-diazo-p-hydroxyesters.     

A Convenient Synthesis of Protected α-Hydroxyacetaldehydes

Starting from 2, 3-O-isopropylideneglycerol (1), a general procedure for the preparation of protected α-hydroxyacetaldehydes has been developed.     

A Convenient Synthesis of Vinyl Epoxides from Glycidic Esters via α-Hydroxy-β,γ-unsaturated Esters

Glycidic esters, upon isomerisation with BF₃.Et₂O yield α-hydroxy-β,γ-unsaturated esters. These are then reduced with LiAlH₄ to vicinal diols which are converted to vinyl epoxides in two steps.     

Synthesis,Characterizations, and Crystal Structures of α-Hydroxyphosphonic Acid Esters

This article describes the synthesis of α-hydroxyphosphonic acid esters using the Pudovik reaction. IR, ¹H NMR, ¹³C NMR, ³¹P NMR, MS, and elemental analysis were employed to confirm their structures. X-ray structure analysis is reported for six compounds. The antibacterial activities of these compounds are also reported.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

A Convenient Synthesis of α-Hydrosyiminoacetonitriles from Aldoximes

Aromatic α-hydroxyiminoacetonitriles can be conveniently prepared by a facile one-pot procedure in high yields involving chlorination of the corresponding aldoximes with tert-butyl hypochlorite followed by reaction with alkali cyanide.     

A Convenient Synthesis of α-Hydroxyiminoacetonitriles From Aldoximes

Aromatic α-hydroxyiminoacetonitriles can be conveniently prepared by a facile one-pot procedure in high yields involving chlorination of the corresponding aldoximes with tert-butyl hypochlorite followed by reaction with alkali cyanide.     

A General Synthesis of α-Substituted Acrylic Esters

During a study of synthetic approaches to various naturally-occurring sesquiterpenes lactones, we developed a new synthesis of the α-methylene-γ-butyrolactone group.¹ This new sequence suggested that it might be applicable to the general synthesis of α-methylenecarbonyl compounds.² This report describes the application to a general synthesis of α-substituted acrylic esters.     

A Convenient Synthesis of α-Functional Alkyl Vinyl Ketones

Reaction of 2-functional alkyl-1,3-diketones with 30% aqueous formaldehyde using aqueous 6-10M potassium carbonate solution as base, afforded a-functional alkyl vinyl ketones in good yields.     

New Synthesis of α-Bromo-α,β-Unsaturated Esters

A synthesis of α-bromo-α,β-unsaturated esters 2 from tert-butyl α-(trimethylsilyl)-α-bromoacetate (1) and carbonyl compounds is described.     

Synthesis of Methyl α-d-Allopyranoside and Methyl α-d-Ribo-hexopyranoside: A Convenient Chemoenzymatic Approach

Abstract

An efficient chemoenzymatic synthesis of methyl α-d-allopyranoside and methyl 3-deoxy-α-d-ribo-hexopyranoside starting from methyl 4,6-O-benzylidene-α-d-glucopyranoside is described.     

A Convenient Synthesis of α,β-unsaturated Nitriles

α,β-unsaturated nitriles were synthesized by the reaction of aldehydes with bromoacetonitrile promoted by tri-n-butylphosphine and zinc.     

Synthesis and Intramolecular Cyclization of ω-Haloalkyl Dithiophosporus Acid Esters

y -Haloalkyl dithiophosphorus acid esters undergo the thermal rearrangement resulting in the corresponding 2-oxo-1,3,2-dithiaphosphacyclanes.     

A New Synthesis of α-Methylene Carbinols

The synthetic utility of α-methylene carbinols has prompted considerable recent preparative interest. However, many of the reported methods¹ lack scope and require reagents or reaction conditions which are incompatible with sensitive functional groups. We report below two closely related methods for the synthesis of α-methylene carbinols which are based on the reductive elimination of β,γ-epoxysulfones. Both methods give the desired products in moderate overall yield in a four-step sequence which is mild and experimentally facile.     

Convenient Synthesis of tert‐Butyl Esters of Indole‐5‐carboxylic Acid and Related Heterocyclic Carboxylic Acids

The tert‐butyl esters of indole‐5‐carboxylic acid and related compounds such as benzofuran‐ and benzothiophene‐5‐carboxylic acid were readily accessed by reacting the appropriate carboxylic acids with tert‐butyl trichloroacetimidate. To obtain the tert‐butyl esters of the 5‐carboxylic acids of 1H‐benzotriazole and 1H‐benzimidazole, position 1 of these heterocycles had to be protected by acetylation prior to reaction with tert‐butyl trichloroacetimidate. Cleavage of the acetyl residue of the obtained intermediates by dilute aqueous NaOH in ethanol led to the desired tert‐butyl 1H‐benzotriazole‐and 1H‐benzimidazole‐5‐carboxylates.