Premium
[4 + 2]‐Cycloadditionen von α, β‐ ungesättigten hydrazonen. Teil3 . Isothiazolo[4,5‐ b ]pyridin‐3(2 H )‐on‐1,1‐dioxide (= 4‐azasaccharine)
Author(s) -
Waldner Adrian
Publication year - 1989
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19890720702
Subject(s) - chemistry , cycloaddition , substituent , solvent , medicinal chemistry , stereochemistry , organic chemistry , catalysis
[4 + 2] Cycloaddition of α, β‐Unsaturated Hydrazones: Isothlazolo[4,5‐ b ]pyridin‐3(2 H )‐on 1,1‐Dioxides (= 4‐Azasaccharine Derivatives) The [4 + 2] cycloaddition of α, β ‐unsaturated hydrazones of type 1 (1‐azabuta‐1,3‐dienes) with isothiazol‐3(2 H )‐on 1,1‐dioxide derivatives 10 affords, depending on the solvent used, picolinamides 15 or 17 , 4,7‐dihydro‐4‐azasaccharine 14 or 4‐azasaccharine derivatives 16 ( Scheme 4 ). The course of the reaction is mainly influenced by the substituent R of the dienophile 10 .