Stereoselective Synthesis of ( E )- and ( Z )-Isocyanoalkenes.

( E )- and ( Z )-isocyanoalkenes were selectively synthesized via the sequential cross coupling of vinyl iodides with formamide, followed by dehydration. The optimal catalyst, generated in situ from Cu I I and trans-N,N' -dimethyl-1,2-cyclohexanediamine, rapidly coupled ( E )- or ( Z )-vinyl iodides with formamide, which minimized the isomerization of the resultant vinyl formamide. The method efficiently provided a range of acyclic, carbocyclic, and heterocyclic isocyanoalkenes; the versatility is illustrated with the selective, stereodivergent syntheses of the diastereomeric isocyanoalkene antibiotics, B371 and E -B371.