Facile, Direct Reaction of Benzaldehydes to 3-Arylprop-2-Enoic Acids and 3-Arylprop-2-Ynoic Acids in Aqueous Medium

Wittig reactions of benzaldehydes, alkanals, and cycloalkanals as well as of acetophenones are carried out with alkoxycarbonyl methylidenetriphenylphosphoranes in 10 w% aqueous NaOH, where the cinnamates and alkenoates produced are hydrolysed in situ and the corresponding acids are obtained after mostly simple extractive work-up, often without employing organic solvents. Under the same conditions, benzaldehydes are reacted with alkoxycarbonyl bromomethy-lidenephosphorane to produce 3-arylprop-2-ynoic acids (arylpropiolic acids).

Visible light induced tandem reactions:An efficient one pot strategy for constructing quinazolinones using in-situ formed aldehydes under photocatalyst-free and room-temperature conditions

A facile tandem route has been developed for constructing quinazolinones from various aminobenzamides and in-situ generated aldehydes.Visible light was found to play a dual role:first oxidizes the alcohol to the aldehyde and then facilitates its cyclization with o-substituted aniline.Furthermore,alcohols are perfe ct alternatives to aldehydes because they are greene r,more available,more economical,more stable,and less toxic tha n aldehydes.The first reaction step continuously provides material for the second step,which effectively reduces loss through volatilization,oxidation,and polymerization of the aldehyde,while avoiding its toxicity.A variety of quinazolinones can be prepared in the presence of visible light without any additional photocatalyst.The developed synthesis protocol proceeds with the merits of mild conditions,broad substrate scope,operational simplicity,a nd high atom efficiency,with an eco-energy source under metal-free,photocatalyst-free,and ambient conditions.

Novel and Efficient One Pot Condensation Reactions between Ketones and Aromatic Alcohols in the Presence of CrO3 Producing α,β-Unsaturated Carbonyl Compounds

We report a new, effective and simple method for preparing a,fl-unsaturated carbonyl compounds by reacting ketones and aromatic alcohols at 56 ℃ in the presence of CrO3 （CrO3 acts as an oxidant and also a catalyst） for around 10 h. The condensation reactions occurred effectively among a wide combination of ketones and alcohols. The procedure is simple and the yields can be high up to 98%. And a probable mechanism is proposed.

An efficient one-pot three-component synthesis and antimicrobial evaluation of tetra substituted thiophene derivatives

A convenient one-pot three-component method for the preparation of tetra-substituted thiophene derivatives has been developed. Reaction ofacetyl acetone 1, phenyl isothiocynate 2 and 2-chloromethyI derivatives 3a-3c in the presence of potassium carbonate afforded the target compounds, namely ethyl 2-（4-acetyl-3-methyl-5-（phenylamino）thiophen-2-yl）-2-oxoacetate derivatives 4a-4e, ethyl 3-（4- acetyl-3-methyl-5-（phenylamino）thiophen-2-yl）-3-oxopropanoate derivatives 4f-4i, di（（4-acetyl-3- methyl-5-phenylamino）thiophen-2-yl）ketone derivatives 4j-4n in reasonable overall yields. The synthesized compounds were screened for antirnicrobial activity. The detailed synthesis, spectroscopic data and antimicrobial activities of synthesized compounds were reported.