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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 convenient and effective synthesis of various novel β-perfluoroalkylated subporphyrins has been developed. β-Trifluoromethylated subporphyrins were efficiently synthesized by the reaction of brominated subporphyrins with FSO 2 CF 2 CO 2 Me/CuI [with or without Pd(dba) 2 ]. Potentially valuable β-perfluoroalkylated, β-monotetrafluorobenzo, and β-monotrifluorobenzo subporphyrins were successfully obtained by a modified sulfinatodehalogenation reaction. Photophysical and electrochemical studies on several typical perfluoroalkylated subporphyrins demonstrated that β-hexakistrifluoromethylated subporphyrins show an obviously red-shifted UV/Vis absorption band that arises from macrocycle nonplanar distortion induced by trifluoromethyl groups, but this distortion is not so severe as that of the corresponding β-octakis(trifluoromethyl)- meso -tetraphenylporphyrin. This was supported by their redox potential data. In addition, β-monotrifluorobenzo subporphyrin exhibits a special fluorescence spectrum of vibronic structure.

S-(fluoroalkyl)diphenylsulfonium salts have been successfully synthesized from the reaction between fluoroalkylsulfinates and triflic anhydride in dichloromethane through a one-pot procedure. These S-(fluoroalkyl)diphenylsulfonium salts have been demonstrated to be effective reagents to fluoroalkylate C-nucleophilic substrates. Ionic substitution and radical or halogenophilic mechanism might be all involved in the reactions.

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.

Difluoro-substituted spirocyclopropaneisoxazolidines were formed by 1,3-dipolar cycloaddition of difluoro(methylene)cyclopropanes (F 2 MCPs) with nitrones in high yields. The [3+2]-cycloaddition reactions exhibited good regioselectivity and high stereoselectivity. The cycloadducts could rearrange further to form highly substituted 3,3-difluorinated tetrahydropyridinols.

A series of fluorinated MESO,β-fused 5,15-diphenyl-porphyrins have been synthesized by the reaction of 5,15-di-phenylporphyrins with fluoroalkyl halides under modified sulfinatodehalogenation reaction conditions through radical cyclization.