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A series of chira
l imines derived from 1-amino-1-deoxya
ldito
ls such as
D-g
lucamine, a rather unexp
loredraw materia
l from the chira
l poo
l, have been serendipitious
ly transformed into a nove
l fami
ly of
N-acety
l-1,3-oxazo
lidines by means of an unexpected acety
lation. The
structure of these substances is supportedby spectroscopic and crysta
llographic data. The acety
lates a
lso trigger a comp
lex dynamic transformation,in which an initia
lly configured trans oxazo
lidine converts into a more stab
le cis-configured derivative.Both isomers can a
lso exist as rotationa
l conformers (
E,
Z) as a consequence of the re
stricted rotationaround the
N-acety
l bond. The barriers to rotation have been determined by variab
le-temperatureexperiments. Overa
ll, this transformation most
like
ly invo
lves the intermediacy of a chira
l iminium ion,which has been documented in the synthesis of nitrogen heterocyc
les, thus exp
laining the experimenta
lfacts.