(TERT-BUTOXYCARBONYLMETHOXYPHENYL)DIPHENYLSULFONIUM TRIFLATE synthesis

Yield:1187544-43-9 94.6%

Reaction Conditions:

in dichloromethane;water; for 3 h;

Steps:

4.1

7 g of the adamantane-1-carboxylic acid 2,2-difluoro-2-sulfoethyl ester sodium salt produced in Synthesis Example 1-(2), and 10 g of diphenyl t-butoxycarbonylmethoxyphenyl sulfonium trifluoromethanesulfonate are dissolved in 100 ml of dichloromethane and 100 ml of water, and the system is allowed to undergo a two-layer reaction with vigorous stirring for 3 hours.After completion of the stirring, an aliquot of the organic layer is removed, and the progress of the reaction is checked by ¹⁹F-NMR. When the reaction goes to completion, the organic layers are combined, the solvent is removed, and the residues are washed with dichloromethane which is a good solvent, and with hexane which is a poor solvent. The solvents are removed, and the residues are dried under reduced pressure. Thus, 12.2 g (yield 94.6%) of adamantane-1-carboxylic acid 2,2-difluoro-2-sulfoethyl ester diphenyl t-butoxycarbonylmethoxyphenyl sulfonium salt was obtained, and the structure of the product was confirmed by ¹H-NMR. The obtained spectrum is presented in FIG. 8.¹H-NMR (chloroform-d₃, internal standard: tetramethylsilane): δ (ppm) 1.48 (s, 9H), 1.67-1.98 (m, 15H), 2.47 (s, 3H), 4.62 (s, 2H), 4.76 (t, 2H), 7.17 (d, 2H), 7.65-7.77 (m, 12H)

References:

US2009/234155,2009,A1 Location in patent:Page/Page column 11