Fluorinated Carbenes

Synthesis of gem‐Difluorinated Cyclopropanes and Cyclopropenes: Trifluoromethyltrimethylsilane as a Difluorocarbene Source

“…However, a [2+1] cycloaddition reaction of difluorocarbene to an alkene or an alkyne has proven to be the most efficient method to date. [4,5] This result has led to considerable efforts in developing reagents that can act as a source of difluorocarbene. Owing to the interaction of the lone pairs of electrons on the fluorine substituents with the carbene center, difluorocarbene is a relatively stabilized carbene species (with a singlet ground state) and is therefore less reactive than other dihalocarbenes.…”

Synthesis of Methylene‐ and Alkylidenecyclopropane Derivatives

“…Difluorocyclopropane derivatives are usually prepared by difluorocarbene addition to alkenes. [21] In this context, a variety of difluorocarbene precursors have been developed but, however, these precursors are either inefficient or difficult to obtain, involving most of the time expensive and/or toxic materials. On the other hand, trimethylsilyl fluorosulfonyldifluoroacetate, which is easily prepared from considerably less expensive materials, has been reported as a highly versatile source of difluorocarbene.…”

C-H Functionalisation Through Singlet Chlorocarbenes Insertions – MP2 and DFT Investigations

“…The halocarbenes and carbenes are important transient intermediates in organic synthesis [2], in organometallic chemistry [3] and in gas phase combustion [4,5]. In the ground state the singlet halocarbenes are stabilized over the triplet carbenes by a large σ -p π separation [6,7,8] and inductive/ mesomeric effects or a combination of both the effects.…”