Facile and Practical Methods for the Sulfonylation of Alcohols Using Ts(Ms)Cl and Me2N(CH2)nNMe2 as a Key Base

Abstract

Several alcohols were smoothly and practically tosylated by two Methods A and B. Method A uses the TsCl/ Me 2 N(CH 2 ) n NMe 2 (n = 3 or 6) reagent and Method B uses TsCl/ Et 3 N/catalytic Me 2 N(CH 2 ) n NMe 2 (n = 3 or 6) reagent. Compared with the traditional Py-solvent method, Method A has the advantages of its much higher reaction rate, operational simplicity, and circumvention of the undesirable side reaction from ROTs to RCl. Method B has the advantage of economy in the use of the amine. Related methanesulfonylations in toluene solvent also proceeded successfully.

Recent applications of the divinylcyclopropane–cycloheptadiene rearrangement in organic synthesis

“…The remaining alcohol moieties were then oxidized to the corresponding keto-aldehyde 185 . A two-step procedure was employed to generate α,β-unsaturated oxindole- N -methoxide 187 [157–158]. Formation of silyl enol ether 188 furnished the desired cis -divinylcyclopropane, which underwent smooth DVCPR under mild conditions to give bridged bicycle 189 .…”

Radiosynthesis and preliminary evaluation of an18F‐labeled tubastatin A analog for PET imaging of histone deacetylase 6

“…To introduce a fluoroethyl moiety, 2-fluoroethyl p-toluenesulfonate (4) was prepared by monofluorination of ethylene di(p-toluenesulfonate) with tetrabutylammonium fluoride (TBAF). We also tried tosylation of 7 using tosyl chloride with triethylamine or N,N,N 0 ,N 0 -tetramethyl-1,3-propanediamine as a base, 45 but we failed to obtain the desired product. 42 For synthesis of 3, 5 was N-fluoroethylated with 4, and then a methylester group was converted to a hydroxamic acid group with hydroxylamine.…”

“…Initially, we attempted to synthesize a tosylated precursor from 5 with ethylene di(p-toluenesulfonate) under the same reaction condition used for the synthesis of 6, but formation of a dimerized by-product, which was bridged with an ethylene group, was mainly observed. We also tried tosylation of 7 using tosyl chloride with triethylamine or N,N,N 0 ,N 0 -tetramethyl-1,3-propanediamine as a base, 45 but we failed to obtain the desired product. A fluorination test of 8 using TBAF in acetonitrile under heating demonstrated formation of 6 (data not shown); therefore, we proceeded to radiosynthesis of [ 18 F]3 using 8 as a precursor.…”

Glycoside Mimics from Glycosylamines: Recent Progress

“…MsCl in the presence of Et 3 N was used for the synthesis of N -benzyl- N -glycosides. For the cyclization of compounds 47f – h which do not cyclize under the present conditions, a catalytic amount of tetramethylethylenediamine (TMEDA) was added as a promoter [83], followed by heating the crude product in MeCN at 85 °C.…”