B. Narsaiah

A SIMPLE AND EFFICIENT METHOD FOR THE SYNTHESIS OF NOVEL TRIFLUOROMETHYL BENZIMIDAZOLES UNDER MICROWAVE IRRADIATION CONDITIONS

ABSTRACT The condensation of trifluoromethyl -o-phenylenediamines and aromatic aldehydes under microwave irradiation on metal halide supported alumina resulted exclusively trifluoromethyl-2-aryl benzimidazoles. *IICT Communication No. 4776.

MICROWAVE ASSISTED KNOEVENAGEL CONDENSATION: A FACILE METHOD FOR THE SYNTHESIS OF CHALCONES *

Microwave irradiation of aromatic aldehydes with acetophenones or malonic acid in presence of anhydrous zinc chloride was resulted exclusively chalcones and cinnamic acids respectively in high yields. *IICT Communication No: 4643.

A novel synthetic route to 2-amino-3-cyano-4-trifluoromethyl-6-substituted pyridines

Abstract 2-Amino-3-cyano-4-trifluoromethyl-6-substituted pyridines have been obtained from 3-cyano-4-trifluoromethyl-6-substituted-2(1H)pyridones via an interesting rearrangement of 2-O-acetamido-3-cyano-4-trifluoromethyl-6-sub-stituted pyridine intermediates.

Palladium (II) catalysed claisen rearrangement: Synthesis of inaccessible N-allyl-2(1H)-pyridones from 2-(allyloxy)pyridines

Abstract 6-Aryl-4-trifluoromethyl-2(1H)-pyridones ( 1 ) yielded O-allylated products ( 3 ) exclusively on allylation. The inaccessible N-allylated products ( 4 ) were synthesised in good yields from the O-allylated products by utilising Pd(II) catalysed [3,3] sigmatropic rearrangement.

Silica sulphuric acid : An efficient and recyclable catalyst for the synthesis of β-acetamido ketones in single pot

Abstract An efficient method has been developed for the synthesis of β‐acetamido ketones by a multicomponent condensation route using sulphuric acid on silica gel as an inexpensive catalyst. Catalyst was recycled without loss of activity.

A simple and facile method for the synthesis of novel 5/7 trifluoromethyl-substituted 4(3H)-quinazolone regioisomers

Abstract The unsymmetrical 1,3-diketones 1 on reaction with malononitrile is resulted an interesting trifunctional intermediates 2 and 3 . The intermediate 2 is hydrolyzed to give 2,6-dicarboxamido aniline 4 which on cyclisation gave two regioisomers of 1,2-dihydro-4(3H)-quinazolinones 5 and 6 . The effect of substituents on compound 4 is characteristic for formation of regioisomers in different proportions. Each regioisomer on dehydrogenation under mild condition using active MnO 2 gave corresponding 4(3H)-quinazolones 7 and 8 , respectively.

A facile method for the synthesis of novel fluorinated pyrido [2′,3′:3,4] pyrazolo [1,5-a] pyrimidines ☆

Abstract The reaction of 3-amino-4-trifluoromethyl-6-substituted pyrazolo [3,4-b] pyridines (1) with active methylene compounds, such as ethoxy methylene malononitrile, ethyl-(ethoxymethylene)cyanoacetate and 1,3-diketones gave exclusively pyrido [2′,3′:3,4] pyrazolo [1,5-a] pyrimidines (2) and (5), respectively in high yields. When compound (1) was reacted with ethoxy methylene diethyl malonate (EMME), intermediate 3-amino (methylenediethylmalonate)-4-trifluoromethyl-6-substituted pyrazolo [3,4-b] pyridines (3) are obtained. The intermediates are further cyclized to give product (4).

Facile syntheses of novel 2-(1,1,1-trifluoroacetonyl) imidazoles, oxazoles, quinazolines and perimidines

Abstract The synthetic utility of trifluoroacetyl ketene diethylacetal has been exploited to build novel imidazoles, oxazoles, quinazolines and perimidine compounds that contain a trifluoroacetonyl group. The products themselves are interesting starting materials for a variety of new compounds.

Efficient and Convenient Method for the Synthesis of Poly Functionalised 4H‐Pyrans

Abstract An efficient single‐pot method for the synthesis of polyfunctionalized 4H‐pyrans using alkaline metal fluoride as a catalyst is described. #IICT Communication No. 040105.

A new synthetic route to fluorinated pyrazolo[3,4-b]pyridines and their use in the preparation of novel pyrido[2′,3′:3,4]pyrazolo[1,5-a]pyrimidines

Abstract A single-step synthesis of 3-amino-4-trifluoromethyl-6-substituted-1H-pyrazolo[3,4-b]pyridines (7) from 2-O-acetamido-3-cyano-4-tri-fluoromethyl-6-substituted pyridines (6) is described, and their use in the synthesis of novel pyrido[2′,3′:3,4]pyrazolo[1,5-a]pyrimidines (8) under microwave irradiation outlined.