Synthesis and chemistry of some 2-aminoethenesulfonyl fluorides. An unusual manganese dioxide oxidation

An efficient preparation of β-dimethylaminovinyl sulfone and sulfoximide, and investigation of their reactivity as dipolarophiles

“…Modest success in preparing new vinyl sulfoximides was achieved with simple amine-exchange reactions. The lack of reactivity of either the enamine or sulfonyl/sulfonimidoyl functions is most likely due to resonance stabilisation of 4 and 5 ( Figure 1); a similar example can be found in the work of Hyatt and Krutak [10].…”

A Simple Protocol for the Stereoselective Construction of Enaminyl Sulfonyl Fluorides

“…However, the convenient synthesis of N -ESF has rarely been accomplished. A cursory index of the literature indicated that only one report involving the synthesis of N -ESF through a manganese dioxide oxidation of the Michael addition product of ESF with amines (Scheme , b). However, the reported conditions provided limited examples and give 2-aliphatic amino ethenesulfonyl fluoride in a low yield (33%) with the promotion of a transition-metal oxide, which largely restrained the further application of N -ESF.…”

Introducing A New Class of Sulfonyl Fluoride Hubs via Radical Chloro‐Fluorosulfonylation of Alkynes

“…Interestingly, when mixing 3 a with different N, O, and S nucleophiles as shown in Scheme 2, selective substitutions of the chloride rather than the fluoride were observed ( 9 a – d ). It is worth mentioning that these selective substitution reactions provide a facile and rapid approach for the synthesis of β‐amino, alkoxy, and sulfenyl‐substituted alkenylsulfonyl fluorides [17] . This unique substitution selectivity at chloride encouraged us to further apply this method to the modification of amino acids, peptides, and drugs by employing BCASF 3 a as a sulfonyl fluoride‐carrier.…”

“…It is worth mentioning that these selective substitution reactions provide af acile and rapid approach for the synthesis of b-amino, alkoxy,a nd sulfenyl-substituted alkenylsulfonyl fluorides. [17] This unique substitution selectivity at chloride encouraged us to further apply this method to the modification of amino acids,p eptides,a nd drugs by employing BCASF 3a as asulfonyl fluoride-carrier.Asshown in Scheme 2A,the thiol residue of cysteine,t he N-terminals of peptides can be selectively modified by 3a to give sulfonyl fluoride 10-13 in good yields under mild reaction conditions.I mportantly,t he reaction can be conducted in PBS buffer solution (pH 8.0), and the cysteine residue can be selectively modified in the presence of S-ATBAa nd dipeptide MeO-Ala-Ala-NH 2 .N o 11 and 12 was detected by 19 FNMR analysis.T his result encouraged us to examined the thiol-selectivity in the presence of various residue groups of amino acids such as alcohol, carboxylic acid, amine,amide,indole,etc.,which also shown excellent selectivity toward thiol (for details,please see Part 9o ft he supporting information). Moreover,t oo ur delight, in the modification of af ifteen-amino acid-peptide (P1)w ith 3a in Tr is buffer (pH 8.0), the HPLC-HRMS analysis also indicated excellent selectivity (Scheme 2B,f or P2, m/z calc.f or C 72 H 112 FN 18 O 27 S 2 [MÀH] À 1743.7381, found 1743.7381).…”