Use of fluoroalkyl as a latent group for internal alkylation: application to the synthesis of bridged tetrahydrofluorenones.
Tetrahydrofluorenones which possess a C9a-fluoroalkyl substituent were efficiently converted to tetrahydrofluorenones which contain a ring bridging C9a-C2. Conditions include a stepwise sequence of conversion to an alkyl bromide followed by treatment with base, and a direct cyclization by treatment with lithium chloride in DMF heated to 150 degrees C.
Parker
Dann L
DL
Department of Medicinal Chemistry, Merck Research Laboratories, Rahway, New Jersey 07065, USA. dann_parker@merck.com
Fried
Amy K
AK
Meng
Dongfang
D
Greenlee
Mark L
ML
D000478:Alkylation; D001952:Bridged-Ring Compounds / Q000138:chemical synthesis; D002384:Catalysis; D003500:Cyclization; D047629:Estrogen Receptor beta / Q000819:agonists; D005449:Fluorenes / Q000138:chemical synthesis*; D006845:Hydrocarbons, Fluorinated / Q000737:chemistry*; D015394:Molecular Structure
D001952:Bridged-Ring Compounds; D047629:Estrogen Receptor beta; D005449:Fluorenes; D006845:Hydrocarbons, Fluorinated