21181-48-6Relevant academic research and scientific papers
Photolysis of alkylhalodiazirines: Two pathways for vinyl halide formation
La Villa, Joseph A.,Goodman, Joshua L.
, p. 5109 - 5112 (1990)
Photoacoustic calorimetry and product studios on the photochemical decomposition of methylhalodiazirines indicate two pathways for the formation of vinyl halides: 1) a [1,2] intramolecular hydrogen shift of the initially formed methylhalocarbene, 2) an excited state pathway which circumvents the ground state carbene. Results suggest that carbene/olefin or carbene/alcohol complexes are not involved in vinyl halide formation.
Rearrangement of alkylchlorocarbenes: 1,2-H shift in free carbene, carbene-olefin complex, and excited states of carbene precursors
Bonneau, Roland,Liu, Michael T. H.,Kim, Kyu Chul,Goodman, Joshua L.
, p. 3829 - 3837 (2007/10/03)
Photolysis of alkylchlorodiazirines (1) in the presence of olefins gives a cyclopropane (3) by addition of the generated carbene to the olefin and a vinyl chloride derivative (2) resulting from a 1,2-H shift rearrangement. This rearrangement may occur either in the carbene or in some excited state, precursor of the carbene (RIES mechanism), or in a 'carbene + olefin complex' on the way to the formation of 3 (COC mechanism). Results obtained by time-resolved photoacoustic calorimetry as well as by thermolysis and photolysis of ClCH2C(N2)Cl and CH3(CH2)2C(N2)Cl in the presence of tetramethylethylene clearly indicate that both the RIES and COC mechanisms play a role but with efficiencies which greatly depend on the nature of the diazirine. Reexamination of the results previously obtained with benzylchlorodiazirines indicates that, for this class of diazirines, the RIES mechanism is temperature dependent and has a very low efficiency at room temperature and below, whereas the nonlinearity of the plots [3]/[2] vs [olefin] is mainly due to the COC mechanism.
