Asymmetric synthesis of new beta,beta-difluorinated cyclic quaternary alpha-amino acid derivatives.
The synthesis of new beta,beta-difluorinated cyclic quaternary alpha-amino acid derivatives 1 in which a ring-closing metathesis reaction (RCM) constitutes the key step is described. The approach employs imidoyl chlorides 3 as fluorinated building blocks, and the overall process involves the stereoselective creation of a quaternary stereocenter. Complete selectivity was achieved when (R)-phenylglycinol methyl ether was used as chiral auxiliary, allowing for the preparation of new six-membered cyclic fluorinated alpha-amino acids as single enantiomers.
Fustero
Santos
S
Departamento de Química Organica, Universidad de Valencia, E-46100 Burjassot, Spain. santos.fustero@uv.es
Sanchez-Roselló
María
M
Rodrigo
Vanessa
V
del Pozo
Carlos
C
Sanz-Cervera
Juan F
JF
Simón
Antonio
A
Ramírez de Arellano
Carmen
C
D000596:Amino Acids / Q000138:chemical synthesis*; D005461:Fluorine / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
D000596:Amino Acids; D005461:Fluorine