Stereospecific bromination-cyclization of spirocyclic cyclohexanones having an isopropylidenedioxy group was found to proceed under thermodynamically controlled conditions, which was applied to the first synthesis of (+/-)-laurencial and its epimer. (C) 1998 Elsevier Science Ltd. All rights reserved.
Iwata, Chuzo; Miyashita, Kazuyuki; Koga, Yasuo, Chemical and pharmaceutical bulletin, 1983, vol. 31, # 7, p. 2308 - 2312