
TY  - JOUR
A1  - Crow, WD 
A1  - McNab, H 
T1  - Synthetic Applications of Intramolecular Insertion in Arylcarbenes. IV. o-Alkoxy-, Dialkylamino- and Alkylthio-1-phenylethylidenes
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1979
VL  - 32
IS  - 1
SP  - 123
EP  - 131
KW  - 
UR  - https://doi.org/10.1071/CH9790123 
N2  - A series of 1-phenylethylidenes, substituted in the ortho-position by alkoxy, dialkylamino and alkylthio side chains containing up to three carbon atoms, has been generated in the gas phase and pyrolysed at 250-750º/0.05-0.30 mm. Carbene insertion to form five-membered heterocyclic rings predominates, with up to 20% Bamford-Stevens insertion, to give the styrenes; little or no formation of six-membered rings is observed. In cases where stereoselective insertion is possible, the trans-disubstituted heterocycle is formed preferentially, the selectivity being greatest in the case of dialkylamino substitution. The mechanisms involved are discussed in terms of transition state geometry. 
ER  -

