1: 1.) oxalyl chloride, Me2SO 2.)Et3N / 1.) CH2Cl2, 15 min, -60 deg C 2.) 0-10 deg C, 5 h 2: 95 percent / dimethylaminopyridine, pyridine / 6 h / 25 °C 3: 1.) zinc dust, Ph3P 2.) pyridine / 1.) CH2Cl2, 15 min, r.t. 2.) CH2Cl2, 30 min r.t. 4: n-butyllithium / tetrahydrofuran; hexane / -78 to 20 deg C 6: 91 percent / Et3N / bis-triphenylphosphine palladium dichloride / dimethylformamide / 1.5 h / 75 °C 7: 95 percent / H2 / Lindlar's catalyst, quinoline / hexane / 0.75 h 8: 2.) AG 50W-X4 resin / 1.) iso-octane, 4 h, reflux 2.) methanol, CH2Cl2, 24 h, r.t. 9: 80 percent / diethyl ether / 0.33 h / -78 °C View Scheme

With  3-chloro-benzenecarboperoxoic acid in  chloroform; water 25 h;  pH 7.8;