Multi-step reaction with 7 steps
1: 1.) tert-BuLi / 1.) ether/pentane, -78 deg C, 70 min, 2.) ether/pentane, -78 deg C, 1 h
2: 91 percent / (TMS)2NLi / tetrahydrofuran / Ambient temperature
3: 97 percent / tetrabutylammonium fluoride / tetrahydrofuran / 0 °C
4: 1.) oxalyl chloride, DMSO, 3.) Et3N / 1.) CH2Cl2, -78 deg C, 15 min, 2.) CH2Cl2, -78 deg C, 25 min, 3.) CH2Cl2, 0 deg C, 25 min
5: 1.) n-BuLi / 1.) hexane/ether, room temperature, 2 h, 2.) hexane/ether, 17 h, room temperature
6: lithium, acetic acid, isoprene / tetrahydrofuran; liquid ammonia / -78 °C
7: 4-DMAP / CH2Cl2 / Ambient temperature
With
dmap; n-butyllithium; oxalyl dichloride; tetrabutyl ammonium fluoride; tert.-butyl lithium; lithium; acetic acid; dimethyl sulfoxide; triethylamine; lithium hexamethyldisilazane; isoprene;
In
tetrahydrofuran; dichloromethane; ammonia;
DOI:10.1016/S0040-4020(01)87241-0