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Controlled Reduction of Carboxamides to Alcohols or Amines by Zinc Hydrides
Derek Yiren Ong1, Zhihao Yen1, Asami Yoshii1
1Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore.
Abstract:
New protocols for controlled reduction of carboxamides to either alcohols or amines were established using a combination of sodium hydride (NaH) and zinc halides (ZnX2 ). Use of a different halide on ZnX2 dictates the selectivity, wherein the NaH-ZnI2 system delivers alcohols and NaH-ZnCl2 gives amines. Extensive mechanistic studies by experimental and theoretical approaches imply that polymeric zinc hydride (ZnH2 )∞ is responsible for alcohol formation, whereas dimeric zinc chloride hydride (H-Zn-Cl)2 is the key species for the production of amines.
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