The reaction is general for primary Nitronates, which yield aldehydes, and secondary ones, which pay ketones. And in fact, the first reported example involved nitroethane in forming acetaldehyde. Although this is essentially a degradative reaction and not a skeleton-building reaction, a reactivity aspect makes the Nef reaction extremely useful.
The Sandmeyer reaction is an organic substitution type reaction used for the synthesis of aryl halide from an aryl diazonium salt. the catalyst used in Sandmeyer reaction is a copper(I) halide like chloride, bromide or iodide ions catalyst. significantly, The reaction include trifluoromethylation, hydroxylation, cyanation, and halogenation type reaction on benzene.