54669-40-8Relevant academic research and scientific papers
High-pressure access to the Δ9-cis - And Δ9-trans-tetrahydrocannabinols family
Minuti, Lucio,Ballerini, Eleonora
supporting information; scheme or table, p. 5392 - 5403 (2011/08/06)
Diels-Alder reactions of a range of 1-(alkoxy/alkyl-substituted phenyl)buta-1,3-dienes with methyl vinyl ketone and methyl acrylate carried out in ethanol as the reaction medium under 9 kbar pressure were investigated. The use of high pressure as the activating method of the Diels-Alder reactions allows the efficient and endodiastereoselective generation of a series of cis-cyclohexenyl-benzene cycloadducts, which are selectively converted into their trans-epimers. The cis-cyclohexenyl-benzenes and trans-cyclohexenyl- benzenes produced are useful precursors for accessing substituted privileged cis-6a,7,8,10a-tetrahydro-6H-benzo[c]chromene and trans-6a,7,8,10a-tetrahydro- 6H-benzo[c]chromene skeletons. The total syntheses of Δ9-cis- tetrahydrocannabinol (THC) and Δ9-trans-THC, through the use of selected Diels-Alder adducts, are described. Finally, a route for obtaining Δ9-trans-THC in both enantiomeric pure forms based on the (S)-(-)-1-amino-2-(methoxymethyl)pyrrolidine (SAMP)-hydrazone method is also reported.
High-pressure diels-alder cycloadditions between benzylideneacetones and 1,3-Butadienes: Application to the synthesis of (R,R)-(-)- and (S,S)-(+)-Δ8-tetrahydrocannabinol
Ballerini, Eleonora,Minuti, Lucio,Piermatti, Oriana
supporting information; experimental part, p. 4251 - 4260 (2010/09/05)
High-pressure Diels-Alder reactions of various alkoxy/alkyl-substituted benzylideneacetones with methyl-1,3-butadienes are reported. Activation by high pressure (8-11 kbar) in combination with the mild Lewis acid HfCl 42THF allows these reactions to efficiently and regioselectively produce a series of ortho-substituted cyclohexenyl-benzene cycloadducts, that are useful precursors for the expeditious construction of the privileged 6,6-dimethyltetrahydro-6H-benzo[c]chromene skeleton. Application to the synthesis of Δ8-trans-THC in both enantiomeric pure forms is based on the successful resolution of selected cycloadduct by the SAMP-hydrazone method.
