Reduction of amides to amines is an attractive subject in organic synthesis. Ca(CH2C6H4NMe2‐o)2(THF)2, an easily accessible main‐group complex, on combination with pinacolborane (HBpin) could serve as a highly active catalyst system in the reduction of primary, secondary and tertiary amides into the corresponding amines. This protocol showed good tolerance for functional groups and heteroatoms, and the aimed products could be obtained in a gram‐scale. The active species in this transformation was supposed to be a calcium hydride.

Significance: The tandem addition-cyclization reaction described in this report represents a highly efficient approach towards 1,3-dihydrobenzofurans and tetrasubstituted furans. The reaction is carried out in a one-pot manner and provides products with good yields and high selectivities. Interestingly, extremely high Z-diastereoselectivity is observed, most likely arising from the subsequent regioselective 5-exo-dig cyclization reaction. Comment:The authors have shown that the reaction proceeds well for a series of aromatic and aliphatic aldehyde substrates. Moreover, different organozinc reagents can be efficiently used for the reaction, which renders this transformation more general. Hopefully, this method can be expanded to other classes of carbonyl-like substrates and the selectivitiy improved.

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