Intramolecular Nicholas reaction: stereoselective synthesis of 5-alkynylproline derivatives.
The intramolecular Nicholas reaction of propargylic alcohols derived from N, N-acyl-diprotected omega-semialdehydes obtained from glutamic acid provided stereoselectively 5-alkynylproline derivatives. The suitable choice of the N-protecting group (tosyl or benzoyl derivative) permitted control of the stereochemistry during the ring formation. Semiempirical calculations of the species involved in the cyclization support the observed stereochemistry.
Hernández
J Nicolás
JN
Instituto Universitario de Bio-Orgánica Antonio González Universidad de La Laguna, La Laguna, Tenerife, Spain.
Ramírez
Miguel A
MA
Rodríguez
Matías L
ML
Martín
Víctor S
VS
D000480:Alkynes / Q000138:chemical synthesis* / Q000737:chemistry; D003500:Cyclization; D015394:Molecular Structure; D011392:Proline / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
D000480:Alkynes; D011392:Proline