Efficient synthesis of B-alkylated oxazaborolidines derived from ephedrine and norephedrine.
[reaction: see text] Representative B-butyl- and B-methyl-1,3,2-oxazaborolidines derived from ephedrine and norephedrine were prepared in good yield and excellent purity by one-pot treatment of B-H oxazaborolidines with the corresponding organolithium reagent and subsequent hydrolysis of the cyclic borohydride intermediate with anhydrous ammonium chloride.
Ortiz-Marciales
Margarita
M
Department of Chemistry, University of Puerto Rico-Humacao, CUH Station, Humacao, Puerto Rico 00791, USA. mr_ortiz@webmail.uprh.edu
González
Eduvigis
E
De Jesús
Melvin
M
Espinosa
Sandraliz
S
Correa
Wildeliz
W
Martínez
Johanna
J
Figueroa
Ruth
R
D000478:Alkylation; D001894:Borohydrides / Q000737:chemistry; D001896:Boron Compounds / Q000138:chemical synthesis*; D004809:Ephedrine / Q000031:analogs & derivatives*; D018020:Lithium Compounds / Q000737:chemistry; D015394:Molecular Structure; D010078:Oxazines / Q000138:chemical synthesis*; D010665:Phenylpropanolamine / Q000031:analogs & derivatives*; D013237:Stereoisomerism
D001894:Borohydrides; D001896:Boron Compounds; D018020:Lithium Compounds; D010078:Oxazines; D010665:Phenylpropanolamine; D004809:Ephedrine