Monoamides

Monoamides are organic compounds that contain a single amide functional group in their structure. An amide consists of a carbonyl group (C=O) directly bonded to nitrogen, with the general form R‑CO‑NR'R''. In a monoamide, this is the only amide unit within the molecule. Based on the substitutions at nitrogen, monoamides are commonly categorized as primary amides (R‑CO‑NH2), secondary amides (R‑CO‑NHR'), and tertiary amides (R‑CO‑NR'R'').

Simple examples include acetamide (CH3‑CO‑NH2) and benzamide (C6H5‑CO‑NH2), as well as tertiary amides such as N,N-dimethylformamide (HCO‑N(CH3)2) and N,N-dimethylacetamide (CH3CH2‑CO‑N(CH3)2). Monoamides occur widely in chemistry as both intermediates and end products. They can be prepared by amidation of carboxylic acids or their derivatives with ammonia or amines using dehydrating coupling methods, or by functional group interconversions from esters, acid chlorides, or nitriles under appropriate conditions.

Properties of monoamides vary with substitution. Primary amides strongly hydrogen-bond, often giving high melting points and distinctive solubility. Many monoamides are polar and useful as solvents (e.g., DMF, DMA) or as building blocks in pharmaceutical and agrochemical synthesis. They are generally more resistant to hydrolysis than esters but can be hydrolyzed to carboxylic acids under acidic or basic conditions.

In summary, monoamides are a broad class defined by a single amide linkage, encompassing diverse compounds used as solvents, reagents, and intermediates in organic synthesis.