1: 100 percent / 1,5-diazabicyclo<5.4.0>undec-5-ene (DBU) / tetrahydrofuran / 0.5 h / 0 °C 2: 1.) N-hydroxysuccinimide, N,N-dicyclohexylcarbodiimide (DCC) / 1.) THF, 15 min, 2.) RT, 3 days 3: 95 percent / sat NaHCO3 aq / 0.67 h / Heating 4: 25 percent / PCl5, CaCO3 / nitromethane / 0.67 h / Heating 5: 61 percent / aluminium amalgam / diethyl ether; H2O / 1 h / Heating 6: 1.) oxalyl chloride, 2.) 4N HCl / 1.) DMF, benzene, reflux, 3.5 min,then RT, 2.) acetone, RT, 5h 7: lithium hydroxyde monohydrate / H2O 8: 57 percent / lithium hydroxide monohydrate / H2O; acetone / 2 h 9: 84 percent / potassium dihydrogen phosphate, 1N LiOH, hog kidney acylase I / H2O / 24 h View Scheme

With  1,5-diazabicyclo[5.4.0]undeca-5-ene in  tetrahydrofuran T=0°C; 0.5 h;