title: A facile and efficient synthesis of 3,3-dimethyl isopropylidene proline from (+)-3-carene.
abstract: A highly efficient and practical route to 3,4-isopropylidene proline I, starting from (+)-3-carene, was developed. The three continuous stereocenters were constructed using the inherent chirality of the starting natural product 2. The overall yield for the 12-step synthesis is 34%. The optimized sequence leading to 1 has been successfully applied on a multigram scale, thereby establishing the practicality of this route.
authors.affiliation: Merck Research Laboratories, 2015 Galloping Hill Road, Kenilworth, New Jersey 07033, USA. latha.nair@spcorp.com
authors.forename: Latha G
authors.initials: LG
authors.lastname: Nair
authors.forename: Anil
authors.initials: A
authors.lastname: Saksena
authors.forename: Raymond
authors.initials: R
authors.lastname: Lovey
authors.forename: Mousumi
authors.initials: M
authors.lastname: Sannigrahi
authors.forename: Jesse
authors.initials: J
authors.lastname: Wong
authors.forename: Jianshe
authors.initials: J
authors.lastname: Kong
authors.forename: Xiaoyong
authors.initials: X
authors.lastname: Fu
authors.forename: Viyyoor
authors.initials: V
authors.lastname: Girijavallabhan
mesh_terms: D000498:Allyl Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D000081008:Bicyclic Monoterpenes; D002384:Catalysis; D002850:Chromatography, Gel; D003500:Cyclization; D008969:Molecular Sequence Data; D015394:Molecular Structure; D039821:Monoterpenes / Q000737:chemistry*; D011392:Proline / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: C549279:3,3-dimethyl isopropylidene proline; D000498:Allyl Compounds; D000081008:Bicyclic Monoterpenes; D039821:Monoterpenes; D011392:Proline; C030218:3-carene