2.3- Dihydro-4//-pyrido oxazinium bromide

The equilibrium mixtures of 3-hydroxy-3-methyl-3,4-dihydro-lH-pyrido [2,l-c][l,4]oxazinium chloride 159a, its 4,4-dideutero derivatives 161a (06PJC1039) and those of 3-hydroxy-3-phenyl-3,4-dihydro-lH-pyrido [2,l-c][l,4]oxazinium bromide 159b and 161b (06JST36) with their ring-opened forms 160 and 162 were characterized by FTIR, 1H, 13C, and 15N NMR spectra in DMSO and D20. 

Treatment of 2-(2-vinyloxyethyl)pyridine with Bra in CCI4 at 0°C gave Tbromomethyl-2,3-dihydro-l//-pyrido[l,2-c][l,3]oxazinium bromide (86KGS1396). 

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