title: (S)-2-chloro-2-fluoroethanoyl isocyanate, a chiral derivative of trichloroacetyl isocyanate.
abstract: Carbamate diastereomers 3b-18b were prepared from easily accessible (S)-2-chloro-2-fluoroethanoyl isocyanate (1) and various secondary chiral alcohols. Compound 1 as a chiral analog of trichloroacetyl isocyanate undergoes the reaction with alcohols very fast, thus blocking the hydroxyl group for the purposes of NMR investigation. Moreover, the correlation of stereochemistry of 3b-18b with their (1)H NMR spectra revealed that the constitution as well as configuration influences regularly the values of chemical shift difference (deltadelta = delta(R) - delta(S)) except for those diastereomers bearing simple alkyl groups in the molecule. Spectral as well as crystallographic data manifest the predominant planar conformation of the central part of the molecule. Due to the good accessibility and high reactivity in particular, the acylisocyanate 1 might be considered, to some extent, an alternative for TAI giving additional information on a compound's spatial structure.
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Prague, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Vodicka
authors.forename: Ludvík
authors.initials: L
authors.lastname: Streinz
authors.forename: Bohumír
authors.initials: B
authors.lastname: Koutek
authors.forename: Milos
authors.initials: M
authors.lastname: Budesínský
authors.forename: Jan
authors.initials: J
authors.lastname: Ondrácek
authors.forename: Ivana
authors.initials: I
authors.lastname: Císarová