1: 85 percent / oxalyl chloride; DMSO; Et3N / CH2Cl2 / 1 h / -78 - -10 °C 2: H2SO4 / diethyl ether; CHCl3 View Scheme

1: With 9-borabicyclo[3.3.1]nonane dimer in tetrahydrofuran T=20°C; 48 h; 2: With sodium hydroxide; dihydrogen peroxide in tetrahydrofuran; ethanol 1 h; Heating; Further stages.;

sodium borohydride in tetrahydrofuran; sodium hydroxide; water

lithium aluminium tetrahydride in tetrahydrofuran 24 h; Heating;

1: 75 percent / potassium tert-butoxide / dimethylsulfoxide / 4 h / 30 °C 2: 1.) aq. mercuric acetate, 2.) aq. sodium hydroxide, sodium borohydride / 1.) THF, 30 deg C, 3 h, 2.) 0 deg C, 1 h View Scheme

1.1: 85 percent / oxalyl chloride; DMSO; Et3N / CH2Cl2 / 1 h / -78 - -10 °C 2.1: H2SO4 / diethyl ether; CHCl3 3.1: 9.56 g / p-TsOH / CHCl3 / 36 h / Heating 4.1: LDA / tetrahydrofuran; hexane / 1 h / -78 °C 4.2: 51 percent / tetrahydrofuran; hexane / 13.5 h / -78 - 20 °C 5.1: 34 percent / LiAlH4 / diethyl ether / 3 h / Heating View Scheme

1.1: 85 percent / oxalyl chloride; DMSO; Et3N / CH2Cl2 / 1 h / -78 - -10 °C 2.1: H2SO4 / diethyl ether; CHCl3 3.1: 9.56 g / p-TsOH / CHCl3 / 36 h / Heating 4.1: LDA / tetrahydrofuran; hexane / 1 h / -78 °C 4.2: 51 percent / tetrahydrofuran; hexane / 13.5 h / -78 - 20 °C View Scheme