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In organic chemistry, the triflyl group (systematic name: trifluoromethanesulfonyl group) is a functional group with the formula R−SO 2 CF 3 and structure R−S(=O) 2 −CF 3. The triflyl group is often represented by –Tf. The related triflate group (trifluoromethanesulfonate) has the formula R−OSO 2 CF 3, and is represented by –OTf. [1]
Its pK a value in water cannot be accurately determined but in acetonitrile it has been estimated as −0.10 and in 1,2-dichloroethane −12.3 (relative to the pK a value of 2,4,6-trinitrophenol (picric acid), anchored to zero to crudely approximate the aqueous pK a scale [2]), making it more acidic than triflic acid (pK a MeCN = 0.70, pK a DCE ...
The tert-butyloxycarbonyl protecting group or tert-butoxycarbonyl protecting group [1] (BOC group) is an acid-labile protecting group used in organic synthesis. The BOC group can be added to amines under aqueous conditions using di- tert -butyl dicarbonate in the presence of a base such as sodium hydroxide :
The trifluoromethyl group is a functional group that has the formula-CF 3. The naming of is group is derived from the methyl group (which has the formula -CH 3), by replacing each hydrogen atom by a fluorine atom. Some common examples are trifluoromethane H– CF 3, 1,1,1-trifluoroethane H 3 C – CF 3, and hexafluoroacetone F 3 C –CO– CF 3.
Ditolylguanidine is a sigma receptor agonist. [1] It is somewhat [2] selective for sigma receptors, but non-selective between the two sigma receptor subtypes, binding to both σ1 and σ2 with equal affinity. [3] It has neuroprotective [4] and antidepressant effects, [5] and potentiates the effects of NMDA antagonists. [6]
Contrary to the popular belief, the CF 3 anion, with [K(18-crown-6)] + as a countercation, was produced and characterized by Prakash and coworkers. [55] The challenges associated with observation of CF 3 anion are alluded to its strong basic nature and its tendency to form pentacoordinated silicon species, such as [Me 3 Si(CF 3) 2] − or [Me 3 ...
For example, n-butyl triflate can be written as CH 3 CH 2 CH 2 CH 2 OTf. The corresponding triflate anion , CF 3 SO − 3 , is an extremely stable polyatomic ion ; this comes from the fact that triflic acid ( CF 3 SO 3 H ) is a superacid ; i.e. it is more acidic than pure sulfuric acid , already one of the strongest acids known.
However, the use of dichloromethane is avoided since it can generate highly explosive azido-chloromethane and diazidomethane. The reaction may also instead be conducted in toluene, [3] acetonitrile, or pyridine. [4] Tf 2 O + NaN 3 → TfN 3 + NaOTf (Tf = CF 3 SO 2) An alternative route starts from imidazole-1-sulfonyl azide. [5]