ChemInform Abstract: Generation and Study of Benzylchlorocarbene from a Phenanthrene Precursor

Autor: Richard P. Johnson, Manisha Nigam, Matthew S. Platz, John P. Toscano, Brett M. Showalter, Mary M. Kirchhoff, Sarah C. Abbot
Rok vydání: 2010
Předmět:
Zdroj: ChemInform. 29
ISSN: 1522-2667
0931-7597
DOI: 10.1002/chin.199847062
Popis: The curved plots of (carbene adduct)/(carbene-rearrangement product) versus carbene trapping agent, tetramethylene [TME], reported with benzylchlorodiazirine 1 have been reproduced. However, with the use of a non-nitrogenous precursor, plots of this type are approximately linear over the range of [TME] employed. Thus, any complex formed between benzylchlorocarbene and TME must collapse to form cyclopropane faster then it can fragment with rearrangement to β-chlorostyrene and TME. Diazirine 1 does photoisomerize to diazo compound 7, but this process is inefficient (φ = 0.075) and is not likely to be responsible for the curvature in plots of adduct/styrene versus [TME] observed with the diazirine precursor. Thus, the second, noncarbene, pathway to β-chlorostyrene is neither a carbene−olefin complex nor a diazo intermediate. It is proposed that the second pathway involves a rearrangement in the excited state of the diazirine, although other explanations cannot be discarded.
Databáze: OpenAIRE