• Greatly increases the rate of ester and thio ester formation in the carbodiimide method of coupling (Steglich esterification): Angew. Chem. Int. Ed., 17, 522 (1978). For similar use in macrolactonizations, see: J. Org. Chem., 50, 2394 (1985), and in carbodiimide peptide coupling reactions: Int. J. Pept. Prot. Res., 18, 459 (1981). For peptide reagents, see Appendix 6.
•
Hypernucleophilic catalyst. Greatly accelerates the acylation of hindered, including tertiary, alcohols; reviews: Angew. Chem. Int. Ed., 17, 569 (1978). Chem. Soc. Rev., 12, 129 (1983). Catalyst for acylation of alcohols using mixed anhydrides of hindered carboxylic acids with methanesulfonic acid: Synth. Commun., 12, 727 (1982), and with mixed carboxylic anhydrides: J. Org. Chem., 50, 560 (1985). In the Yamaguchi method of macrocyclic lactonization the mixed anhydride formed with 2,4,6-Trichlorobenzoyl chloride, L14159 is cyclized with 2 equiv. of DMAP; high dilution conditions are not required: Bull. Chem. Soc. Jpn., 52, 1989 (1979). For improved method in a high yield synthesis of erythronolide A, see: J. Org. Chem., 55, 7 (1990).• For a brief feature on the uses of this reagent in synthesis, see: Synlett, 1568 (2003). Review of developments in the search for optimal reactivity and selectivity with 4-(dialkylamino)pyridines: Angew. Chem. Int. Ed., 43, 5436 (2004).
• Effective catalyst for transesterification of ?-keto esters in toluene: J. Org. Chem., 50, 3618 (1985), and for smooth decarboalkoxylation of enolizable ?-keto esters in toluene containing a small amount of water: J. Org. Chem., 54, 3474 (1989). Under these conditions, other bases (N,N-dimethylaniline, pyridine, tetra-n-pentylammonium bromide) are ineffective.
•
Catalyst in a simple preparation of N-Boc-amides, using Di-tert-butyl dicarbonate, A14708: Acta Chem. Scand. B, 40, 745 (1986); and also of N-Boc-pyrroles: Org. Synth. Coll., 9, 121 (1998).• Reacts with thionyl chloride to form the chlorosulfinyl chloride, an effective reagent for the conversion of acids to their acid chlorides: Synth. Commun., 12, 1139 (1982), and for the dehydration of aldoximes to nitriles: Synthesis, 472 (1983).
• Also useful as a catalyst for various alkylations. For use in formation of trityl ethers, see: Tetrahedron Lett., 95, (1979); extension to mono- and di-methoxytrityl ethers: Tetrahedron Lett., 21, 3899 (1980); J. Org. Chem., 47, 571 (1982); Chem. Lett., 15 (1982); J. Am. Chem. Soc., 104, 1316 (1982). Useful in silylation of alcohols to give TBDMS ethers: Tetrahedron Lett., 99, (1979).
Highly toxic (T+)
Corrosive (C)
Toxic (T)
Flammable (F)
