An Efficient One-Pot Synthetic
Method for 2,4-Disubstituted 7-Arylpyrido[4,3-d]pyrimidines from 2,4-Disubstituted
6-(Arylethynyl)pyrimidine-5-carbaldehydes and tert-Butylamine
The First Tandem Acetalization/5-<i>exo</i>-<i>dig</i> Cyclization of 6-Phenylethynylpyrimidine-5-carbaldehydes: Efficient Synthesis of 5-Alkoxy-(7<i>Z</i>)-7-benzylidene-5<i>,</i>7<i>-</i>dihydrofuro[3,4-<i>d</i>]pyrimidines
The first example of catalyst-free tandem acetalization/5-exo-dig cyclization reactions of 6-phenylethynylpyrimidine-5-carbaldehydes is presented. Efficient novel synthesis of 5,7-dihydrofuro[3,4-d]pyrimidine core is described.
Study on the cyclization of 6-arylethynylpyrimidine-5-carbaldehydes with tert-butylamine: microwave versus thermal preparation of pyrido[4,3-d]pyrimidines
Thermal and microwave initiated cyclization of 2,4-disubstituted 6-arylethynylpyrimidine-5-carbaldehydes with tert-butylamine has been studied. A novel high-yielding preparation of 2,4-disubstituted 7-arylpyrido[4,3-d]pyrimidines has been developed. The intermediate compounds were isolated and possible mechanism of the reactions is discussed. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.
Tandem reactions of 6-phenylethynylpyrimidine-5-carbaldehydes with alcohols: regioselective synthesis of 5-alkoxy-(7Z)-7-benzylidene-5,7-dihydrofuro[3,4-d]pyrimidines and 5-alkoxy-7-phenyl-5H-pyrano[4,3-d]pyrimidines
An efficient and versatile tandem processes of acetalisation and cycloisomerization reactions have been developed for the reactions of 6-phenylethynylpyrimidine-5-carbaldehydes. The influence of the catalyst and role of the substituent in the position 4 of the pyrimidine ring have been studied. Regioselective synthesis of 5,7-dihydrofuro[3,4-d]pyrimidine and pyrano[4,3-d]pyrimidine cores is described. (C) 2009 Elsevier Ltd. All rights reserved.