biostudies-literatureBachollet SPEngineering and Physical Sciences Research Council12889-93https://www.ebi.ac.uk/biostudies/studies/S-EPMC4313684biostudies-literatureUnknown20(40)The aza-Diels-Alder cycloaddition of 1,2,4-triazines with alkynes offers a rapid and convenient method for the synthesis of highly substituted pyridines, but often requires harsh conditions and long reaction times. The present study offers a solution to these limitations by use of a temporary tether established by a Lewis acid-base complexation of in situ generated alkynylboranes and triazines bearing a Lewis basic donor. The cycloaddition reactions take place within 20 min at 40 °C and provide direct access to a broad range of pyridines with complete and predictable regiocontrol. The carbonboron bond can be further functionalised by cross-coupling allowing further functionality to be introduced after cycloaddition.Chemistry (Weinheim an der Bergstrasse, Germany)Development of a mild and versatile directed cycloaddition approach to pyridines.PMC4313684EP/D03213X/1Cocker DCBachollet SPHarrity JPVivat JFAdams HfalseDevelopment of a mild and versatile directed cycloaddition approach to pyridines.The aza-Diels-Alder cycloaddition of 1,2,4-triazines with alkynes offers a rapid and convenient method for the synthesis of highly substituted pyridines, but often requires harsh conditions and long reaction times. The present study offers a solution to these limitations by use of a temporary tether established by a Lewis acid-base complexation of in situ generated alkynylboranes and triazines bearing a Lewis basic donor. The cycloaddition reactions take place within 20 min at 40 °C and provide direct access to a broad range of pyridines with complete and predictable regiocontrol. The carbonboron bond can be further functionalised by cross-coupling allowing further functionality to be introduced after cycloaddition.2014-01-01T00:00:00Z2014 Sep2026-05-29T20:24:34.35Z2019-03-27T01:44:25ZS-EPMC43136842514548810.1002/chem.201403916