Triethylamine Trifluoromethanesulfonic acid

Alkyl esters of trifluoromethanesulfonic acid, commonly called triflates, have been prepared from the silver salt and an alkyl iodide, or by reaction of the anhydride with an alcohol (18,20,21). Triflates of the 1,1-dihydroperfluoroalkanols, CF2S020CH2R can be prepared by the reaction of perfluoromethanesulfonyl fluoride with the dihydroalcohol in the presence of triethylamine (22,23). Triflates are important intermediates in synthetic chemistry. They are among the best leaving groups known, so they are commonly employed in anionic displacement reactions. 

Aniline allowed to react at -78° with trifluoromethanesulfonic acid anhydride and triethylamine in methylene diloride -> N-phenyltriflamide. Y 97%. - The protective group can be removed by reduction. F. e. and triflating agent, also Gabriel-type synthesis of prim, amines from halides via triflamides, s. J. B. Hendrickson and R. Bergeron, Tetrah. Let. 1973, 3839. 

Trifluoromethanesulfonic acid, l,l,l,4,4,4-hexamethyl-2,2,3,3-tetraphenyltetrasilane (1), pentane, a solution of methylmagne-sium chloride in diethyl ether, hexane, acetyl chloride, 2-propanol, triethylamine. 

A suspension of 2 in pentane was obtained by treatment of 1 (410 mg, 802 pmol) with trifluoromethanesulfonic acid (722 mg, 4.81 mmol) in pentane (7 mL) at 20°C as described above. 2-Propanol (289 mg, 4.81 mmol) and triethylamine (482 mg, 4.76 mmol) were added to the stirred suspension of 2 at 0°C in a single portion. After the reaction mixture was stirred at 20°C for 30 min, hexane (5 mL) was added, the precipitate was removed by filtration, and the solvent of the filtrate was removed under reduced pressure to give 5 (334 mg, 95%) as a colorless solid. 

Beccalli et al. reported a new synthesis of staurosporinone (293) from 3-cyano-3-(lH-indol-3-yl)-2-oxo propionic acid ethyl ester (1464) (790). The reaction of 1464 with ethyl chlorocarbonate and triethylamine afforded the compound 1465, which, on treatment with dimethylamine, led to the corresponding hydroxy derivative 1466. The triflate 1467 was prepared from 1466 by reaction with trifluoromethanesulfonic anhydride (Tf20) in the presence of ethyldiisopropylamine. The palladium(O)-catalyzed cross-coupling of the triflate 1467 with the 3-(tributylstannyl)indole 1468 afforded the vinylindole 1469 in 89% yield. Deprotection of both nitrogen atoms with sodium ethoxide in ethanol to 1470, followed by photocyclization in the presence of iodine as the oxidizing agent provided the indolocarbazole 1471. Finally, reductive cyclization of 1471 with sodium borohydride-cobaltous chloride led to staurosporinone (293) in 40% yield (790) (Scheme 5.248). 

Abbreviations DMF, A,A-dimethylformamide DMT, 4,4 -dimethoxytrityl HPLC, high-pressure liquid chromatography NPG, n-pentenyl glycoside TEA, triethylamine TCA, trichloroacetic acid THF, tetrahydrofuran TMSOTf, trimethysilyl trifluoromethanesulfonate. 

Trifluoromethanesulfonic anhydride s. under Ph PO Methanesulfonic acid j triethylamine... 

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