Multi-step reaction with 8 steps
1: 100 percent / conc. H2SO4 / methanol / 16 h / Heating
2: 1.) CuI, 2.) (TMS)Cl / 1.) THF, RT, 5 min, 2.) THF, from -78 deg C, to RT, 9 h
3: pig liver esterase
4: oxalyl chloride, DMF / CH2Cl2 / 0.33 h / Ambient temperature
5: Et3N / tetrahydrofuran
6: 93 percent / 2,3-dichloro-5,6-dicyanobenzoquinone / tetrahydrofuran; H2O
7: 94 percent / Et3N / CH2Cl2
8: 84 percent / aq. LiOH*H2O / tetrahydrofuran
With
lithium hydroxide; copper(l) iodide; chloro-trimethyl-silane; oxalyl dichloride; sulfuric acid; triethylamine; N,N-dimethyl-formamide; 2,3-dicyano-5,6-dichloro-p-benzoquinone;
In
tetrahydrofuran; methanol; dichloromethane; water;
DOI:10.1021/ja00141a004