A facile and efficient synthesis of 3,3-dimethyl isopropylidene proline from (+)-3-carene.
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.
Nair
Latha G
LG
Merck Research Laboratories, 2015 Galloping Hill Road, Kenilworth, New Jersey 07033, USA. latha.nair@spcorp.com
Saksena
Anil
A
Lovey
Raymond
R
Sannigrahi
Mousumi
M
Wong
Jesse
J
Kong
Jianshe
J
Fu
Xiaoyong
X
Girijavallabhan
Viyyoor
V
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
C549279:3,3-dimethyl isopropylidene proline; D000498:Allyl Compounds; D000081008:Bicyclic Monoterpenes; D039821:Monoterpenes; D011392:Proline; C030218:3-carene