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A Ph3P/ICH2CH2I-promoted dehydroxylative cyanation of alcohols has been developed. In contrast to previous dehydroxylative cyanation methods that can suffer from several limitations, such as the use of transition metals or moisture-sensitive Lewis acids, this protocol features convenient operations, mild reaction conditions, and the use of cheap and widely available reagents.

Despite intensive studies on the synthesis of 3-formylindoles, it is still highly desirable to develop efficient methods for the formylation of indoles, due to the shortcomings of the reported methods, such as inconvenient operations and/or harsh reaction conditions. Here, we describe a Ph3P/ICH2CH2I-promoted formylation of indoles with DMF under mild conditions. A Vilsmeier-type intermediate is readily formed from DMF promoted by the Ph3P/ICH2CH2I system. A one-step formylation process can be applied to various electron-rich indoles, but a hydrolysis needs to be carried out as a second step in the case of electron-deficient indoles. Convenient operations make this protocol attractive.

A large number of efficient cyanation methods have been developed because of the wide range of applications of nitriles, but conventional methods usually suffer from the need for a toxic cyanation reagent. Although difluorocarbene chemistry has received increasing attention, the use of difluorocarbene as a sources of the nitrile carbon for nitrile groups remains largely unexplored. We describe a difluorocarbene-based cyanation of aryl iodides promoted by a cheap copper source, Cu(NO3)2·2.5H2O, under an air atmosphere. Ph3P+CF2CO2 –, an easily available and shelf-stable difluorocarbene reagent, and NaNH2 are used as the carbon source and the nitrogen source for the nitrile group, respectively. The cyanation protocol is attractive because no toxic reagent is used and performing the reactions under an air atmosphere is operationally convenient.

Ph3P/I–-promoted dichlorination and dibromination of epoxides by using XCH2CH2X (X = Cl or Br) as the halogen source and reaction solvent is described. All reagents are widely available and easy to handle, and mild conditions and operational simplicity make this protocol attractive.

A new precursor of N-heterocyclic carbene bearing push-pull substituents has been synthesized by the quaternization of 1-(4-methoxyphenyl)-imidazole. Unexpected reactions between the carbene generated in situ and aromatic aldehydes or acrylates were observed resulting in the formation of imidazole derivatives.