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This article discusses the synthesis and reactions of a new diazoalkane reagent called (diazomethyl)dimethylphosphine oxide (Me₂P(O)CHN₂). Ukrainian chemists have extensively studied various diazoalkanes relevant to medicinal chemistry over the past two decades. The research article by O. O. Grygorenko and co-workers provides more information on the synthesis and [3+2] cycloaddition reactions of this novel diazoalkane reagent. The article also includes artwork by Vitalii Boklashchuk. [Extracted from the article]

Five CF3-substituted 3-azabicyclo[ n.1.0]alkanes were synthesized by CuCl-mediated trifluoromethylcyclopropanation reaction of the corresponding cyclic enamides with CF3CHN2. [ABSTRACT FROM AUTHOR]

The [3+2] cycloaddition of CF3CHN2, generated in situ, with electron-deficient alkenes/alkynes affords CF3-substituted pyrazolines/pyrazoles in quantitative yields. The one-pot three-component reaction between CF3CH2NH2 ·HCl, NaNO2, and the substrate proceeds at room temperature in dichloromethane/water. [ABSTRACT FROM AUTHOR]

Two isomeric conformationally restricted analogues of 4-trifluoromethylpiperidine were designed. The synthesis was performed in four steps from commercially available N-benzylmaleimide. The key reaction was the [3+2] cycloaddition between trifluoromethyldiazomethane and N-benzylmaleimide. [ABSTRACT FROM AUTHOR]

The 1,3-dipolar cycloaddition of azide generated from hydrochloride (II) and alkynes or alkenes with at least one strong electron-withdrawing group allows the synthesis of various pyrazoles as well as Δ1- [e.g. (VII)] and Δ2-pyrazolines [e.g. (V)] in excellent yields with high regio- and diastereoselectivity. [ABSTRACT FROM AUTHOR]

A safe and efficient method for the in-situ preparation of (diazomethyl)dimethylphosphine oxide - a hereto unexplored diazoalkane reagent - is developed. The method is based on the diazotization of the corresponding P(O)Me 2 -substituted amine (readily available in multigram quantities) in non-aqueous media. The protocol provides the target product as ca. 1.5 M CHCl 3 solution which is stable at -18 °C. The utility of the synthesized diazoalkane is illustrated by its [3+2] cycloaddition with electron-poor alkynes and alkenes providing the corresponding P(O)Me 2 -substituted pyrazoles and pyrazolines with moderate to good efficiency. In this view, the title compound represents and an important extension of medicinally relevant phosphine oxide reagents., (© 2024 Wiley‐VCH GmbH.)