Reagent for activation of carboxylic acids to nucleophiles: J. Org. Chem., 63, 4248 (1998). Peptide coupling reagent: Synthesis, 917 (1987). With N-methylmorpholine forms the quaternary chloride (DMTMM) which is a valuable low-cost coupling agent in solid-phase peptide synthesis: Synlett, 275 (2000). For a reexamination of the use of the reagent in peptide coupling, see: Tetrahedron Lett., 42, 4161 (2002); Similarly, carboxylic acids are converted to Weinreb amides by reaction with N,O-dialkyl hydroxylamines: J. Org. Chem., 66, 2534 (2001). Can also be used for the esterification of carboxylic acids: Synthesis, 593 (1999). The intermediate active esters can be hydrogenolyzed, providing a simple method for reduction of acids to aldehydes; at higher pressures, further reduction to the alcohol can be effected: J. Org. Chem., 64, 8962 (1999).