36967-85-8Relevant articles and documents
Decarboxylation with Carbon Monoxide: The Direct Conversion of Carboxylic Acids into Potent Acid Triflate Electrophiles
Kinney, R. Garrison,Arndtsen, Bruce A.
supporting information, p. 5085 - 5089 (2019/04/01)
We report a new strategy for the conversion of carboxylic acids into potent acid triflate electrophiles. The reaction involves oxidative carbonylation of carboxylic acids with I2 in the presence of AgOTf, and is postulated to proceed via acyl hypoiodites that react with CO to form acid triflates. Coupling this chemistry with subsequent trapping with arenes offers a mild, room temperature approach to generate ketones directly from broadly available carboxylic acids without the use of corrosive and reactive Lewis or Bronsted acid additives, and instead from compounds that are readily available, stable, and functional group compatible.
Asymmetric synthesis of complicated bicyclic and tricyclic polypropanoates via the double Diels-Alder addition of 2,2′-ethylidenebis[3,5-dimethylfuran]
Marchionni, Chiara,Vogel, Pierre
, p. 431 - 472 (2007/10/03)
A new, non-iterative method for the asymmetric synthesis of long-chain and polycyclic polypropanoate fragments starting from 2,2′-ethylidenebis[3,5-dimethylfuran] (2) has been developed. Diethyl (2E,5E)-4-oxohepra-2,5-dienoate (6) added to 2 to give a single meso-adduct 7 containing nine stereogenic centers. Its desymmetrization was realized by hydroboration with (+)-IpcBH2 (isopinocampheylborane), leading to diethyl (1S,2R,3S,4S,4aS,7R,8R,8aR,9aS,10R,10aR)-1,3,4,7,8,8a,9,9a-octahydro-3 -hydroxy-2,4,5,7,10-pentamethyl-9-oxo-2H-10H-2.4a:7.10a-diepoxyanthracene -1,8-dicarboxylate ((+)-8: 78% e.e.). Alternatively, 7 was converted to meso-(1R,2R,4R,4aR,5S,7S,8S,8aR,9aS,10s,10aS)-1,8-bis(acetoxymethyl) -1,8,8a,9a-tetrahydro-2,4,5,7,10-pentamethyl-2H-10H-2.4a:7.10a -diepoxyanthracene-3,6,9(4H,5H,7H)-trione (32) that was reduced enantioselectively by BH3 catalyzed by methyloxazaborolidine 19 derived from L-diphenylprolinol giving (1S,2S,4S,4aS,5S,6R,7R,8R,8aS,9aR,10R,10aS)-1,8-bis(acetoxymethyl) -1,8,8a,9a-tretrahydro-6-hydroxy-2,4,5,7,10-pentamethyl-2H,10H-2.4a:7.10a -diepoxyanthracene-3,9(4H,7H)-dione ((-)-33: 90% e.e.). Chemistry was explored to carry out chemoselective 7-oxabicyclo[2,2,1]heptanone oxa-ring openings and intra-ring C-C bond cleavage. Polycyclic polypropanoates such as (1R,2S,3R,4R,4aR,5S,6R,7S,8R,9R,10R,11S,12aR)-1-(ethoxycarbonyl) -1,3,4,7,9,10,11,12,12a-decahydro-3,11-dihydroxy-2,4,5,7,9-pentamethyl-12 -oxo-2H,5H-2,4a:6,9:6,11-triepoxybenzocyclodecene-10,8-carbolactone (51). (1S,2R,3R,4R,4aS,5S,7S,8R,9R,10R,12S,12aS)-1,10-bis(acetoxymethyl) tetradecahydro-8-(methoxymethoxy)-2,4,5,7,9-pentamethyl-3,9-bis ([2-(trimethylsilyl)ethoxy]methoxy)-6,11-epoxycyclodecene-4a,6,11,12-tetrol ((+)-83), and (1R,2R,3R,4aR,4bR,5S,6R,7R,8R,8aS,9S,10aR)-3,5-bis(acetoxymethyl) -4a,8a-dihydroxy-1-(methoxymethoxy)-2,6,8,9,10a-pentamethyl-2,7-bis ([2-(trimethysilsyl)ethoxy]methoxy)dodecahydrophenanthrene-4,10-dione (85) were obtained in few synthetic steps.
Benzoyl Trifluoromethanesulfonate. A Mild Reagent for the Benzoylation of Sterically Hindered Hydroxyls
Brown, Lindsey,Koreeda, Masato
, p. 3875 - 3880 (2007/10/02)
Benzoyl trifluoromethanesulfonate (BzOTf) is a highly efficient reagent for the benzoylation of a variety of alcohols under mild conditions.These include hindered secondary and tertiary hydroxyls, phenols, and α-glycols.Sensitive functionality is stable when the reaction is performed in the presence of pyridine.Several unique rearrangements of Lewis acidsensitive compounds were also effected.
Carboxylic Trifluoromethanesulfonic and Methanesulfonic Anhydrides, Synthesis and Dissociation Tendency
Effenberger, Franz,Epple, Gerhard,Eberhard, Joachim K.,Buehler, Ulrich,Sohn, Erich
, p. 1183 - 1194 (2007/10/02)
Carbonyl chlorides 1 react with silver trifluoromethanesulfonate (2) and silver methanesulfonate (6) to give carboxylic trifluoromethanesulfonic anhydrides 3 and carboxylic methanesulfonic anhydrides 7, resp., in good yields; the anhydrides 3 may be synth
The Synthesis and Some Reactions of N-Methylnitrilium Trifluoromethanesulphonate Salts
Booth, Brian L.,Jibodu, Kehinde O.,Proenca, M. Fernanda
, p. 1151 - 1153 (2007/10/02)
N-Methylnitrilium trifluoromethanesulphonate (triflate) salts, prepared from nitriles and methyl triflate, have been shown to be useful reagents for the synthesis of aromatic ketimines and ketones, amidinium, imidate, and thioimidate salts, benzimidazoles, benzoxazoles, benzothiazoles, quinazolinones, and 1,2,4-triazolinium salts.