118070-40-9Relevant academic research and scientific papers
Diazo Compounds, 70. - Intramolecular Cycloaddition of 5-(Diazomethyl)-5H-benzocycloheptenes - Partial Step of a New Benzosemibullvalene synthesis
Regitz, Manfred,Boehshar, Manfred,Arenz, Stefan,Heydt, Heinrich
, p. 565 - 576 (2007/10/02)
Electrophilic diazoalkane substitution of the (diazomethyl)phosphoryl compounds 13a-d with the 7-alkoxybenzocycloheptenylium perchlorates 8a-e yields the 7-alkoxy-5-(diazomethyl)-5H-benzocycloheptenes 15a-l, which generally isomerize quickly by intramolecular cycloaddition to the tetracycles 19a-l.The 7-isomers 14, formed also in the primary substitution process, can be detected by 1H-NMR spectroscopy.By thermal nitrogen elimination, 19a, b, e and h are transformed into the tetracycles 21a-d.In the case of 19i, k, and l the formation of the tricyclic compounds is accompanied by an additional hetero Cope rearrangement (-> 22a-c).The reaction of the lithiated diazomethyl compounds 24a and b with 7-morpholinobenzocycloheptenylium perchlorate (23) after chromatographic workup leads to the ketones 26a and b. - Keywords: Benzosemibullvalene/ Cycloaddition/ 5H-Benzocycloheptene, 5-(diazomethyl)-/ Electrophilic diazoalkane substitution
