4443-91-8Relevant academic research and scientific papers
Access to the naphthylcarbene rearrangement manifold via isomeric benzodiazocycloheptatrienes
Bonvallet, Paul A.,Todd, Eric M.,Kim, Yong Seol,McMahon, Robert J.
, p. 9031 - 9042 (2007/10/03)
Irradiation (λ = 670 or >613 nm) of 4,5-benzodiazocycloheptatriene (15), matrix isolated in argon at 10 K, produces primarily 2,3-benzobicyclo[4.1.0]hepta-2,4,6-triene (9) accompanied by small amounts of triplet 4,5-benzocycloheptatrienylidene (2) and 2-naphthylcarbene (10). A reversible photoequilibrium is established in which 9 is converted to 10 at λ = 290 nm and then regenerated at λ = 360 nm. Similarly, matrix-isolated 2,3-benzodiazocycloheptatriene (16) produces 4,5-benzobicyclo[4.1.0]hepta-2,4,6-triene (11) at λ = 670 or >613 nm, but without detection of 2,3-benzocycloheptatrienylidene (4). Irradiation of 11 at λ = 290 nm induces ring opening to triplet 1-naphthylcarbene (12), which, in turn, cyclizes back to 11 at λ = 342 or >497 nm. The diazo compounds and photoproducts are characterized by IR, UV/visible, and ESR spectroscopy, where appropriate, and by comparison of the experimental and B3LYP/6-31G* calculated IR spectra for each species. Alternate rearrangement products such as allenes 6, 7, and 8 are not detected in the photolysis of either diazo compound.
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
THE OXIDATION OF BENZOTROPYLIUM CATION
Pomerantz, Martin,Swei, Gwo-Shin
, p. 3027 - 3030 (2007/10/02)
Oxidation of benzotropylium (1) fluoborate with Na2O2 and KO2 gives the benzotropones, 5 and 6, as the major products with no naphtalene (9) or other ring contracted products formed.Oxidation with m-chloroperoxybenzoic acid produces a small amount of naphtaldehydes (10 and 11) and even less naphtalene, along with the benzotropones, while oxidation with H2O2 and t-butyl peroxyacetate gives slightly more of the ring contracted naphtaldehydes than benzotropones, in addition to a small quantity of naphtalene.All reactions produce some 1,2-benzotropolidine (8).
