Giant N-heterocyclic carbene-containing macrocycles for cobalt-catalysed hydroboration of alkynes.

Giant N-heterocyclic carbene-containing organic macrocycles larger than "Texas-sized" molecular boxes have been synthesized and structurally characterized. The new macrocycles were employed for the Co-NHC promoted syn -selective hydroboration of alkynes with good stereo- and regioselectivity.