Organic reaction where amide is converted to Amine or Aldehyde
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
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]
Amines from other hydride sources
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]
Noncatalytic routes to aldehydes
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.
References
^ a b Nishimura, Shigeo (2001). Handbook of Heterogeneous Catalytic Hydrogenation for Organic Synthesis (1st ed.). New York: Wiley-Interscience. pp. 406– 411. ISBN 9780471396987 .
^ March, Jerry (1985). Advanced Organic Chemistry: Reactions, Mechanisms, and Structure (3rd ed.). New York: Wiley. ISBN 9780471854722 . OCLC 642506595 .
^ Mitsudome, Takato; Miyagawa, Kazuya; Maeno, Zen; Mizugaki, Tomoo; Jitsukawa, Koichiro; Yamasaki, Jun; Kitagawa, Yasutaka; Kaneda, Kiyotomi (2017-08-01). "Mild Hydrogenation of Amides to Amines over a Platinum-Vanadium Bimetallic Catalyst" . Angewandte Chemie International Edition . 56 (32): 9381– 9385. doi :10.1002/anie.201704199 . PMID 28649715 .
^ Zhang, Yue; Zhang, Fan; Li, Lin; Liu, Fei; Wang, Aiqin (2022-10-07). "Highly Chemoselective Reduction of Amides to Amines over a Ruthenium‐Molybdenum Bimetallic Catalyst" . ChemistrySelect . 7 (37). doi :10.1002/slct.202203030 . ISSN 2365-6549 . S2CID 252725710 .
^ Pennetier, Alex; Hernandez, Willinton Y.; Kusema, Bright T.; Streiff, Stéphane (2021-08-25). "Efficient hydrogenation of aliphatic amides to amines over vanadium-modified rhodium supported catalyst" . Applied Catalysis A: General . 624 : 118301. doi :10.1016/j.apcata.2021.118301 . ISSN 0926-860X . S2CID 238850541 .
^ Cope, Arthur C.; Ciganek, Engelbert (1959). "N,N-Dimethylcyclohexylmethylamine". Organic Syntheses . 39 : 19. doi :10.15227/orgsyn.039.0019 .
^ Wilson, C. V.; Stenberg, J. F. (1956). "Laurylmethylamine". Organic Syntheses . 36 : 48. doi :10.15227/orgsyn.036.0048 .
^ Moffett, Robert Bruce (1953). "2,2-Dimethylpyrrolidine". Organic Syntheses . 33 : 32. doi :10.15227/orgsyn.033.0032 .
^ Park, Chung Ho; Simmons, Howard E. (1974). "Macrocyclic Diimines: 1,10-Diazacylooctadecane". Organic Syntheses . 54 : 88. doi :10.15227/orgsyn.054.0088 .
^ Seebach, Dieter; Kalinowski, Hans-Otto; Langer, Werner; Crass, Gerhard; Wilka, Eva-Maria (1983). "Chiral Media for Asymmetric Solvent Inductions". Organic Syntheses . 61 : 24. doi :10.15227/orgsyn.061.0024 .
^ Ookawa, Atsuhiro; Soai, Kenso (1986). "Mixed solvents containing methanol as useful reaction media for unique chemoselective reductions within lithium borohydride". The Journal of Organic Chemistry . 51 (21): 4000– 4005. doi :10.1021/jo00371a017 .
^ Zhou, S.; Junge, K.; Addis, D.; Das, S.; Beller, M. (2009). "A Convenient and General Iron-Catalyzed Reduction of Amides to Amines". Angewandte Chemie International Edition in English . 48 (50): 9507– 9510. doi :10.1002/anie.200904677 . PMID 19784999 .
^ Taber, Douglass F (5 June 2006). "The Boger Route to (-)-Vindoline" . Org. Chem. Highlights . Discussion of (12)→(13).
^ Leighty, M. W.; Spletstoser, J. T.; Georg, Gunda I. (2011). "Mild Conversion of Tertiary Amides to Aldehydes Using Cp2 ZrHCl (Schwartz's Reagent)" . Org. Synth. 88 : 427– 437. doi :10.1002/0471264229.os088.39 . ISBN 978-0471264224 .
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