Ylide formation from the reaction of carbenes and carbenoids with heteroatom lone pairs

Tandem Brook Rearrangement/Silicon Polonovski Reaction <i>via</i> Oxidative Generation of Ammonium Ylides

“…Undesirable side reactions, most likely associated with the presence of these strong bases, have been reported, including the Hofmann elimination and 1,2 rearrangement 23,24 . Therefore, weaker bases or milder reaction conditions compatible with a large variety of functional groups are still desired.…”

DFT investigation on mechanism of dirhodium tetracarboxylate-catalyzed O-H insertion of diazo compounds with H2O

“…One is that Rh(II) carbene formed from α-diazo carbonyl compounds takes a direct insertion into O-H bond similar to the concerted C-H insertion. However, this process was considered to be impossible due to the absence of similar reactivity/selectivity outcomes in this pathway [13][14][15]. A recent work reported the kinetic data of Rh(II)-catalyzed insertion of diazo compounds into the O-H band of a series of phenols [16].…”

“…An alcoholic oxonium ylide may react with other nucleophilic components such as aldehyde to form nucleophilic addition products [18][19][20][21][22][23], or perform a rapid 1,2-hydrogen shift reaction in the absence of nucleophilic components [14,15,18,19,24,25]. All these reactions can proceed directly through Rh(II) complexassociated oxonium ylides or through free oxonium ylides derived from Rh(II) complex-associated ylides via direct decomposition.…”

Ab Initio and DFT Investigations of the Mechanistic Pathway of Singlet Bromocarbenes Insertion into C-H Bonds of Methane and Ethane

“…How structural factors (bond angle, electron-withdrawal by induction and electron-donation by resonance) influence the relative stabilities of these states is still under scrutiny [1]. The synthetic organic chemistry [2], organometallic chemistry [3] and other areas, principally; the ArndtEistert chain homologation procedure, the Rimer-Tiemann reaction (formylation of phenols), cyclopropanation of alkenes [4] and subsequent rearrangements, [5] ketene and allene [6] preparation, synthesis of strained ring systems, ylide generation and subsequent rearrangements, cycloaddition reactions [7] and photoaffinity labeling. [8] are some of the vital fields of wide applications of the carbenes and halocarbenes…”