Thermal and Photochemical Reactions of 1,2-Annelated Barrelenes and Hydrobarrelenes in the presence of transition-metal carbonyls
作者:Latchezar S. Trifonov、Alexander S. Orahovats
DOI:10.1002/hlca.19890720404
日期:1989.6.14
The [Co2(CO)8]-mediated retro-Diels-Alder reaction of the annelated barrelenes 1 afforded the 1H-indol-2(3H)-one derivatives 3 (Scheme 1), while the hydrobarrelene 4a, under the same conditions, was converted to the anilide 6 (Scheme 2); 4b remained unaffected. The direct irradiation of 1 led to the annelated cyclooctatetraenes 7 (Scheme 3). On irradiation in the presence of excess of [Fe(CO)5], 1a
Intramolecular Cyclizations of Allenic Acylureas and -Amides
作者:Latchezar S. Trifonov、Alexander S. Orahovats
DOI:10.1002/hlca.19870700130
日期:1987.2.4
Allenic acids are found to add to dicyclohexylcarbodiimide affording, in the presence of Et2NH, the 4H-1,3-oxazin-4-ones 5via4. Under neutral conditions, they add to diaryl- or pyridyl(cyclohexyl)carbodiimides and triphenylketene imine to give the corresponding tricyclo[5.2.2.01,5]undeca-4,8,10-trien-3-ones 7, 8, 9, and 12. The allenic phenyl ester 13a dimerises, on heating in a [2+2] head-to-head