A search for dichlorocarbene ether solvent interactions
作者:Stanislav I. Presolski、Adelajda Zorba、Dasan M. Thamattoor、Eric M. Tippmann、Matthew S. Platz
DOI:10.1016/j.tetlet.2003.11.009
日期:2004.1
The absolute rate constant of reaction of dichlorocarbene with pyridine and with tetramethylethylene was determined in Freon-113 (CF2ClCFCl2), dioxane, and tetrahydrofuran. No evidence of specific solvation was obtained.
Chlorofluorocarbene: First UV Observation of a Dihalocarbene in Solution
作者:Robert A. Moss、Jingzhi Tian、Ronald R. Sauers、Christopher Skalit、Karsten Krogh-Jespersen
DOI:10.1021/ol701804m
日期:2007.9.1
Chlorofluorocarbene (ClCF), generated by laser flash photolysis of chlorofluorodiazirine, absorbs at 368 nm in pentane. Absolute rate constants are reported for ClCF additions to several alkenes and pyridine. ClCF is less reactive toward alkenes than CCl(2), and it does not react rapidly with oxygen. Pertinent computational studies are included.
作者:John E. Chateauneuf、Richard P. Johnson、Mary M. Kirchhoff
DOI:10.1021/ja00164a056
日期:1990.4
Dichlorocarbene is the cornerstone of singlet carbene reactivity. Moss has thoroughly characterized carbenic selectivity in cyclopropanation reactions. The reactivity of any singlet carbene (:CXY) may be standardized by comparison of its reactivity toward a standard set of alkenes with that of chlorocarbene (:CClsub 2}). Amazingly, however, the absolute kinetics of this important reactive intermediate
Laser Flash Photolysis Study of Alkylhalocarbenes Generated from Non-Nitrogenous Precursors
作者:Marc Robert、Igor Likhotvorik、Matthew S. Platz、Sarah C. Abbot、Mary M. Kirchhoff, and、Richard Johnson
DOI:10.1021/jp972464y
日期:1998.2.1
Previously we have studied the photochemistry of alkylchlorodiazirines using laser flash photolysis methods and the pyridine ylide technique (White et al. J. Org. Chem. 1992, 17, 2841). The yield of trappable carbene was found to be a sensitive function of the alkylcarbene structure. This was attributed to ring opening of the diazirine to form a biradical which could suffer rearrangement, in addition to fragmentation to a carbene. It was also possible to explain the data in terms of a carbene-pyridine complex which can either rearrange or collapse to an ylide. In this work, alkylchlorocarbenes are generated from phenanthridenes. The results do not rule out the intermediacy of a carbene-pyridine complex; however, if this species is formed, it does not rearrange to chloroalkene in competition with collapse to form an ylide. This study reduces the urgency with which to postulate carbene-olefin complexes (Tomioka et al. J. Am. Chem. Soc. 1984, 106, 454).