phenylthiomethyl propyl carbamate and the suspension was stirred at 70 u00b0 c 400 mbar for 4 hours the mixture was cooled to 0 u00b0 c the ph was adjusted to 1 by adding hydrochloric acid and the isopropanol was evaporated the suspension was filtered and the residue was recrystallized from toluene to give 2 18 g 75 isomerically pure methyl 1r 2s 3 chloro 2 hydroxy 1 phenylthiomethyl propyl carbamate m p 113 114 u00b0 c ir kbr 3389 m and 3327 m nh oh 1695 s c u2550 o 1537 s amide ii ms ei 289 35 m a mixture of 2 90 g of methyl 1r 2s 3 chloro 2 hydroxy 1 phenylthiomethyl propyl carbamate 0 8 g sodium hydroxide 20 ml toluene and 10 ml of water was stirred at 40 u00b0 c for 2 hours the organic layer was washed with water and the solvent evaporated the residue containing methyl r 1 s oxiran 2 yl 2 phenylthio ethyl carbamate was mixed with 12 ml of ethanol and 2 38 g of decahydro 4as 8as isoquinoline 3 s n tert butyl carboxamide and heated at reflux temperature for 5 10 hours the solvent was evaporated and the residue partitioned between water and dichloromethane the organic layer was evaporated to give 4 4 g 90 of methyl 1r 2r 1 phenylthiomethyl 3 3s 4as 8as 3 tert butoxycarbamoy decahydro isoquinol 2 yl 2 hydroxypropyl carbamate ir kbr 3410 m and 3320 m nh oh 1715 s and 1660 s c u2550 o 1550 s amide ii a suspension of 4 92 g of methyl 1r 2r 1 phenyl thiomethyl 3 3s 4as 8as 3 tert butoxycarbamoyl decahydroisoquinol 2 yl 2 hydroxy propyl carbamate and 2 69 g of.