Benzobicyclo[4.1.0]hepta-2,4,6-trienes

West, Paul R.; Mooring, Anne M.; McMahon, Robert J.; Chapman, O. L.

doi:10.1021/jo00358a029

Cited by 26 publications

(26 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our results on the singlet naphthylchlorocarbene photochemical ring-closures parallel observations of Chapman, 9 McMahon, 10 and co-workers on the parent triplet 1-and 2naphthylcarbenes. In particular, under matrix isolation conditions, the naphthylcarbenes appear to photochemically only cyclize to the corresponding cyclopropenes, which in turn only photochemically ring-open back to the carbenes.…”

Section: Methodssupporting

confidence: 89%

“…Although benzobicycloheptatriene 2 is a logical intermediate between 1 and its rearrangement product 3, and has received the support of highlevel ab initio calculations, 2a,b this species has never been directly observed. However, Chapman and co-workers 9 reported that broad-band irradiation of matrix isolated diazo-precursors to carbenes 5 and 7 produced directly the corresponding benzobicycloheptatrienes 6 and 8. McMahon and Albrecht 10 later showed that more careful irradiation of 2-diazomethylnaphthalene gave 7 in inert matrices, characterizable by IR, UV/vis, and EPR.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Matrix isolation and photochemistry of 1- and 2-naphthylchlorocarbene

Rempała¹,

Sheridan²

1999

J. Chem. Soc., Perkin Trans. 2

View full text Add to dashboard Cite

We have for the first time characterized the 1-and 2-naphthylchlorocarbenes by IR and UV/vis spectroscopy in N 2 matrices at 10 K. Although evidence suggests the presence of predominantly only one geometric isomer in the case of the 1-naphthylchlorocarbene, the IR and UV/vis spectra of the 2-naphthylchlorocarbene indicate two distinct conformations. With selective irradiation, the longer-wavelength absorbing s-Z-isomer of 2-naphthylchlorocarbene can be photochemically driven to the alternate s-E conformation. Irradiation of the 1-and 2-naphthylchlorocarbenes induces cyclization to 7-chloro-4,5-benzobicyclo[4.1.0]hepta-2,4,6-triene and 7-chloro-2,3-benzobicyclo[4.1.0]hepta-2,4,6-triene, respectively. The cyclization can be reversed by irradiation at shorter wavelengths.Our results on the singlet naphthylchlorocarbenes photochemical ring-closures parallel observations of Chapman, McMahon, and co-workers on the parent triplet 1-and 2-naphthylcarbenes (

show abstract

Section: Methodssupporting

confidence: 89%

Section: Introductionmentioning

confidence: 99%

Matrix isolation and photochemistry of 1- and 2-naphthylchlorocarbene

Rempała¹,

Sheridan²

1999

J. Chem. Soc., Perkin Trans. 2

View full text Add to dashboard Cite

show abstract

“…[11,12] The equilibrium between arylcarbenes and cycloheptatetraenes was not only observed for the parent C 7 H 6 system but also for tolylcarbenes, [13][14][15] phenylhalocarbenes, [16] and naphthylcarbenes. [17][18][19][20][21] Similar ring expansions were also observed in heteroarylcarbenes (e.g., in pyridylcarbenes). [22] The unusual thermochemistry and photochemistry of diphenylcarbene 5 have been investigated in great detail.…”

Section: Introductionsupporting

confidence: 66%

“…Warmuth and Marvel were even able to stabilize allene 2 at room temperature inside a hemicarcerand . The equilibrium between arylcarbenes and cycloheptatetraenes was not only observed for the parent C 7 H 6 system but also for tolylcarbenes, phenylhalocarbenes, and naphthylcarbenes . Similar ring expansions were also observed in heteroarylcarbenes (e.g., in pyridylcarbenes) …”

Section: Introductionmentioning

confidence: 70%

1‐Phenyl‐1,2,4,6‐cycloheptatetraene: the missing intermediate of the diphenylcarbene to fluorene rearrangement

Costa

Sander

2014

J of Physical Organic Chem

View full text Add to dashboard Cite

The photochemistry of diphenylcarbene 5, matrix-isolated in argon at 3-5 K was investigated by UV-Vis, IR, and EPR spectroscopy. Although carbene 5 proved to be stable toward broadband UV irradiation, it slowly rearranges to 1-phenyl-1,2,4,6-cycloheptatetraene 8 during irradiation with the intense light of a 445-nm diode laser. Other intermediates were not observed. Allene 8 is the key intermediate that was missing in the proposed mechanism of the rearrangement of 5 to f luorene 7.

show abstract

“…Spectroscopic detection of benzobicyclo[4.1.0]hepta-2,4,6-trienes was provided by Chapman and co-workers in 1986. 39 These results are summarized in Scheme 16. Irradiation of the naphthyldiazomethanes matrix isolated in argon at 15 K yielded, in each case, the benzobicyclo[4.1.0]hepta-2,4,6-triene.…”

Section: Ch Mementioning

confidence: 97%