42495-69-2

Upstream product

• 81967-89-7 β-santalene 
• 50-00-0 formaldehyd 
• 1530-32-1 ethyltriphenylphosphonium bromide 
• 73838-31-0 3-(2exo-methyl-3-methylidene-bicyclo<2.2.1>hept-2-yl)propanal 
• 69667-88-5 ethyl 3-(2-exo-methyl-3-methylenebicyclo<2.2.1>hept-2-yl)propanoate 
• 73838-28-5 ethyl 3-(anti-1,7-dimethyl-2-(acetylamino)bicyclo<2.2.1>hept-7-yl)propanoate 
• 41414-75-9 (+)-α-Santalylacetat 
• 69486-16-4 3-oxatricyclo<6.2.1.0^2,7>undec-4-ene 
• 60547-05-9 3exo-(3-hydroxypropyl)-bicyclo<2.2.1>heptan-2exo-ol 
• 37876-51-0 (+/-)-epi-β-santalene 
• 498-66-8 norbornene 
• 1754-88-7 ethylenetriphenylphosphorane 
• 27548-52-3 (E/Z)-ethyl 2-methyl-5-(2exo-methyl-3-methylidene-bicyclo<2.2.1>hept-2-yl)-2-pentenoate 

Relevant academic research and scientific papers

Radical cyclizations leading to the bicyclo[2.2.1]heptane framework: A new radical approach to (±)-(Z)-β-santalol

Tandem radical cyclizations of acyclic iodides, including [3-(2-iodoethyl)-6,10-dimethyl-undeca-5,9-dien-1-ynyl]-dimethylphenylsilane lead in good yields to bicyclo[2.2.1]heptane derivatives. The cascade relies on two sequential radical-mediated 5-exo-cyclizations. The radical approach is illustrated with the total synthesis of racemic-(Z)-β-santalol. The results are remarkable, two fused rings and one stereogenic center are formed in a single operation. A new 'coordinated' hydride appeared to be useful in the cascade.

Cyclopropane Ring Cleavage in the α-Santal Series, I. - The Absolute Configurations of (-)-β-Santalol, (+)-epi-β-Santalol, and (E)-(-)-β-Santalol

Cyclopropane cleavage of (+)-α-santalyl acetate (1b) by treatment firstly with HCl/CHCl3 at -50 deg C and secondly with basic alumina resulted in (-)-β-santalyl acetate (2b) and (+)-epi-β-santalyl acetate (3b).The identity with 2b, 3b, isolated from east indian sandalwood oil, was demonstrated by 1H-, 13C-NMR, and ORD spectra.This result defines the absolute configurations of the β-santalols 2a, 3a, and 4a.

Stereoselective Syntheses of (+/-)-epi-β-Santalene and (+/-)-epi-β-Santalol

Stereoselective syntheses of (+/-)-epi-β-santalene (1) and (+/-)-epi-β-santalol (2), minor constituents of East Indian sandalwood oil, are described.The starting material for both syntheses is the tricyclic hemiacetal 4, readily accessible in two steps from norbornene.

East Indian Sandalwood Oil. 2. Stereoselective Synthesis of (+/-)-Epi-β-santalene and (+/-)-Epi-β-santalol

Acid-catalyzed rearrangement of γ-lactone 6 in the presence of acetonitrile provides a mixture of amide acids, which are readily separated as their ethyl esters 18-20.The major product 18, when subjected to fragmentation, provides esters 21 and 22 (92percent and 8percent, respectively).The structure of 21 has been confirmed by its conversion, via aldehyde 23, to (+/-)-epi-β-santalene (8).Similarly, the structure of 22 has been confirmed by its conversion to (+/-)-α-santalene (3). (+/-)-Epi-cis-β-santalol (9), (+/-)-epi-trans-β-santalol (10), and (+/-)-dihydroepi-β-santalol (11) have also been prepared via aldehyd 23.