Abstract
Pyridines have been formed by heating azabicyclo[3.2.0]hept-2-en-4-ones in toluene. The generation of a 3-azacyclopentadienone intermediate via a [2 + 2]-cycloreversion is proposed as the key step. A Diels-Alder reaction of a styrene, extrusion of carbon monoxide, and loss of hydrogen then gives the pyridine. The process parallels the well-known synthesis of benzenes from cyclopentadienones. The azabicyclo[3.2.0]hept-2-en-4-ones were synthesized from the reaction between readily available cyclopropenones and 1-azetines, in which the cyclopropenones behave as all-carbon 1,3-dipolar equivalents.
Original language | English |
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Pages (from-to) | 126-129 |
Number of pages | 4 |
Journal | Organic Letters |
Volume | 14 |
Issue number | 1 |
Early online date | 21 Dec 2011 |
DOIs | |
Publication status | Published - 6 Jan 2012 |