A unique rhodium-catalyzed rearrangement process: isomerization of an alkyne to a 1,3-diene with concomitant migration of a formyl group. An expeditious route to dienals from readily available 4-alkynals.
In CH2Cl2, [Rh(BINAP)]BF4 catalyzes the isomerization of 4-alkynals to dienals with excellent regio- and stereoselectivity; this new process compares favorably with previously reported methods for the synthesis of this class of compounds; a possible pathway for this unusual rearrangement is provided.
Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Ken
K
Tanaka
Gregory C
GC
Fu
D000447:Aldehydes / Q000138:chemical synthesis*; D000466:Alkadienes / Q000138:chemical synthesis*; D002384:Catalysis; D005421:Flavoring Agents / Q000737:chemistry; D007536:Isomerism; D010476:Perfume / Q000737:chemistry; D012238:Rhodium / Q000737:chemistry
D000447:Aldehydes; D000466:Alkadienes; D005421:Flavoring Agents; D010476:Perfume; D012238:Rhodium