Pyrrole Chemistry. The Cyanovinyl Aldehyde Protecting Groups
Paine, J.B., Woodward, R.B., and David Dolphin
J. Org. Chem.
Protection of pyrrole aldehyde groups with either Me or Et cyanoacetate or malononitrile gave the corresponding cyanovinyl derivatives which are stable toward a variety of acids, oxidants, and reductants. Removal of the protecting groups with aqueous base regenereates the parent aldehyde.