Amide reduction

Amide reduction is a reaction in organic synthesis where an amide is reduced to either an amine or an aldehyde functional group.^[1][2]

Catalytic hydrogenation can be used to reduce amides to amines; however, the process often requires high hydrogenation pressures and reaction temperatures to be effective (i.e. often requiring pressures above 197 atm and temperatures exceeding 200 °C).^[1] Selective catalysts for the reaction include copper chromite, rhenium trioxide and rhenium(VII) oxide or bimetallic catalyst.^[3][4][5]

Reducing agents able to effect this reaction include metal hydrides such as lithium aluminium hydride,^{[6][7][8][9][10]} or lithium borohydride in mixed solvents of tetrahydrofuran and methanol.^[11]

Iron catalysis by triiron dodecacarbonyl in combination with polymethylhydrosiloxane has been reported.^[12]

Lawesson's reagent converts amides to thioamides, which then catalytically desulfurize.^[13]

Some amides can be reduced to aldehydes in the Sonn-Müller method, but most routes to aldehydes involve a well-chosen organometallic reductant.

Lithium aluminum hydride reduces an excess of N,N-disubstituted amides to an aldehyde:^{[citation needed]}

R(CO)NRR' + LiAlH₄ → RCHO + HNRR'

With further reduction the alcohol is obtained.

Schwartz's reagent reduces amides to aldehydes,^[14] and so does hydrosilylation with a suitable catalyst.

• Amide reduction @ organic-chemistry.org