z-logo
Premium
A convenient route for the synthesis of pyrazolo[3,4‐ d ]pyrimidine, pyrazolo[3,4‐ b ][1,6]naphthyridine and pyrazolo[3,4‐ b ]quinoline derivatives
Author(s) -
Jachak Madhukar N.,
Avhale Appasaheb B.,
Medhane Vijay J.,
Toche Raghunath B.
Publication year - 2006
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570430506
Subject(s) - chemistry , acetonitriles , cyclohexanone , quinoline , formylation , phenanthridine , hydrazine (antidepressant) , cyclopentanone , dimedone , medicinal chemistry , annulation , pyrimidine , tetralone , formamide , dehydrogenation , stereochemistry , organic chemistry , catalysis , chromatography , acetonitrile
Friedländer condensation of 5‐aminopyrazole‐4‐carbaldehydes 1 with formamide 2a or benzamide 2b gave pyrazolo[3,4‐ d ]pyrimidine derivatives 3 . Cyclocondensation of 1 with cyclopentanone, N ‐benzyl‐4‐piperidone and 6‐methoxy‐1‐tetralone yielded cyclopenta[ b ]pyrazolo[4,3‐ e ]pyridines 4 , pyrazolo[3,4‐ b ]‐[1,6]naphthyridines 5 and benzo[ h ]pyrazolo[3,4‐ b ]quinolines 6 , respectively. Analogous condensation of cyclohexanone 7a or 2‐methyl‐1‐cyclohexanone 7b with 1 afforded pyrazolo[3,4‐ b ]quinoline derivatives 8a‐d . Heating 1 with dimedone furnished pyrazolo[3,4‐ b ]quinolinone derivatives 9 . Vilsmeier‐Haack formylation of 9 yielded a mixture of two compounds 10 and 11 . Further bispyrazolo[3,4‐ b :4,3‐ f ]‐quinolines 12a, b were obtained on cyclocondensation of 11a, b with phenyl hydrazine.

This content is not available in your region!

Continue researching here.

Having issues? You can contact us here
Accelerating Research

Address

John Eccles House
Robert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom