TY - JOUR
T1 - Mass spektrometric studies on the formation of chiral N-sulphonylated oxazaborolidinones
AU - Nevalainen, Vesa
AU - Mansikka, Timo
AU - Kostiainen, Risto
AU - Simpura, Ilkka
AU - Kokkonen, Juha
PY - 1999
Y1 - 1999
N2 - The formation of N-tosyl-2-phenyl-1,3,2-oxazaborolidin-5-one 1 as a result of a condensation reaction between N-tosyl valine 2 and phenyl boronic acid was studied as a model of the formation of chiral oxazaborolidines used as Lewis acidic catalysts for various enantioselective syntheses. Intermediates of the formation of 1 along with those arising from further reactions (of 1) were investigated by electrospray ionization mass spectrometry (ESI-MS). Results of the study indicate that one phenyl boronic acid may react with one or two molecules of 2 and/or with one or two molecules of phenyl boronic acid. In addition, side-products implying dephenylation of 1 and self-condensation of phenyl boronic acid (formation of triphenylboroxine) were found.
AB - The formation of N-tosyl-2-phenyl-1,3,2-oxazaborolidin-5-one 1 as a result of a condensation reaction between N-tosyl valine 2 and phenyl boronic acid was studied as a model of the formation of chiral oxazaborolidines used as Lewis acidic catalysts for various enantioselective syntheses. Intermediates of the formation of 1 along with those arising from further reactions (of 1) were investigated by electrospray ionization mass spectrometry (ESI-MS). Results of the study indicate that one phenyl boronic acid may react with one or two molecules of 2 and/or with one or two molecules of phenyl boronic acid. In addition, side-products implying dephenylation of 1 and self-condensation of phenyl boronic acid (formation of triphenylboroxine) were found.
U2 - 10.1016/S0957-4166(98)00479-0
DO - 10.1016/S0957-4166(98)00479-0
M3 - Article
SN - 0957-4166
VL - 10
SP - 1
EP - 5
JO - Tetrahedron: Asymmetry
JF - Tetrahedron: Asymmetry
IS - 1
ER -