697298-84-3Relevant academic research and scientific papers
Stereoselective Synthesis of Carane-Type Hydroxythiols and Disulfides Based on Them
Banina,Sudarikov,Slepukhin,Frolova,Kuchin
, p. 240 - 247 (2016)
Isomeric 10-sulfanylcaran-4-ols and 4-sulfanylcaran-3-ols were synthesized and used to prepare disulfides in high yields.
Stereoselective synthesis of carane-based aminodiols as chiral ligands for the catalytic addition of diethylzinc to aldehydes
Szakonyi, Zsolt,Csillag, Kinga,Fueloep, Ferenc
scheme or table, p. 1021 - 1027 (2011/09/20)
Key intermediate epoxy alcohol 4 was prepared regio- and stereoselectively from (+)-3-carene 1 via carene oxide 2 and (-)-trans-allyl alcohol 3. The lithium perchlorate-catalysed ring opening of 4 with secondary and primary achiral and chiral amines resulted in primary, secondary and tertiary aminodiols. Aminodiols 5-14 were applied as chiral catalysts in the enantioselective addition of diethylzinc to benzaldehyde, resulting in (R)- and (S)-1-phenyl-1-propanol with moderate enantioselectivity. N-Benzyl, N-methyl, and (S)- and (R)-N-methylbenzyl derivatives 7 and 10-13 were transformed into 1,3-oxazines 17-21 via highly regioselective ring closures. When 17-21 were applied as chiral catalysts in the addition of diethylzinc to aromatic and aliphatic aldehydes, high chiral induction in the tricyclic catalysts was observed. The effects of the substituents on the nitrogen of the aminodiols and 1,3-oxazines were studied in detail; the best enantioselectivity was observed in the case of N-methylbenzyl-substituted oxazine 19.
Syntheses and reactions of allyl phenylselenides. A convenient method of the allyl methylcarbamates synthesis
Scianowski,Tafelska-Kaczmarek
, p. 529 - 534 (2008/09/19)
Allyl phenylselenides from terpene systems are convenient precursors for the synthesis of the terpene allyl alcohols and allyl methylcarbamates. Using optically active allyl phenylselenides corresponding optically active oxygen and nitrogen derivatives were obtained. A new one-step method of the allyl methylcarbamates synthesis from allyl phenylselenides was described.
Synthesis of chiral thienylpyridines from naturally occurring monoterpenes: Useful ligands for cyclometallated complexes
Gianini, Michel,Von Zelewsky, Alex
, p. 702 - 706 (2007/10/03)
On treatment with ammonium acetate, α,β-unsaturated ketones or aldehydes can easily undergo condensation with acetylpyridinium salts (Krohnke reaction). Four 'thienylpyridine' ligands, derived from (-)-β-pinene, (+)-camphor, (+)-3-carene and (+)-2-carene, were prepared according to this method. The multistep syntheses to get (1R,5R)-3-methylenenopinone (5), (+)-3-methylenecamphor (10), (-)-3-caren-10-al (15) and (1S,6R)-7,7-dimethyl-3-methylenebicyclo[4.1.0]heptan-2-one (18) are also described.
Regioselective Routes to Nucleophilic Optically Active 2- and 3-Carene Systems
Paquette, Leo A.,Ross, Robert J.,Shi, Yao-Jun
, p. 1589 - 1598 (2007/10/02)
Commercially available (+)-3-carene (4) is shown to be capable of efficient conversion to vinyl bromides 28, 46, and 49 and to vinyl stannane 44.All four compounds stem from (+)-3-norcaranone (23), an optically pure ketone best prepared by epoxidation of 4, followed by oxirane ring opening, acetylation, ozonolysis, and CrCl2-promoted reduction.The strong proclivity exhibited by 23 to enolize in the cyclopropyl carbinyl sense is used to advantage to gain entry to 28 and 44.Remarkably, the tosylhydrazone of (+)-3-norcaranone (45) is distinguished from its ketoneprogenitor 23 by its capacity for highly regioselective deprotonation from the alternative α-position.The crossover has made possible synthetic access to 46 and 49.Other chemistry of this class of compounds is also presented, inluding a route to 51, a vinyl bromide epimeric to 49.Especially relevant to future work in the ingenol area is the ability of these molecules to serve as nucleophiles.Several reactions involving 28 are provided as exemplary of this property.
Transformations of 3-carene oxide at rhenium-containing catalysts
Manukov, E. N.,Bazhina, G. N.
, p. 106 - 110 (2007/10/02)
The transformations of 3-carene oxide at rhenium-containing catalysts were studied.The introduction of rhenium into the catalytic system significantly increases the reaction rate and leads to the formation of compounds not previously encountered in the products from the isomerization of 3-carene oxide, i.e., 3-carene, 3(10),4-caradiene, 3,3,6-trimethylcycloheptanone, and 3-caren-10-ol.
Acid-catalysed Terpenylations of Olivetol in the Synthesis of Cannabinoids
Crombie, Leslie,Crombie, W. Mary L.,Jamieson, Sally V.,Palmer, Christopher J.
, p. 1243 - 1250 (2007/10/02)
Examination of the toluene-p-sulphonic acid-catalysed reaction of (1S,2S,3R,6R)-(+)-trans-car-2-ene epoxide with olivetol shows that, inconsistently with the accepted mechanism, (3R,4R)-(-)-o- and -p-cannabidiols are produced as well as (3R,4R)-(-)-Δ1- and Δ6-tetrahydrocannabinols.Evidence is now presented that, as in Petrzilka's reaction employing chiral p-mentha-2,8-dien-1-ols, the reacting species is the delocalised (4R)-p-mentha-2,8-dien-1-yl cation (9).Similar terpenylation using (1S,3S,4R,6R)-(+)-trans-car-3-ene epoxide shows that besides the reported (-)-Δ6-THC, o- and p-cannabidiols, Δ1-THC and Δ4,8-iso-THC can also be produced.The nature of the products, the chirality, and the characteristics of the reaction implicate again the delocalised cation (9).Its formation via Kropp-type rearrangement is excluded and a pathway leading to (4R)-p-mentha-2,6,8-triene, which on protonation gives (9), is proposed.Protonated on C-8, the triene can be trapped and isolated as (4R)-p-mentha-2,6-dien-8-ol.The latter, made in (+/-)-form from citral, proved to be an excellent terpenylating agent for producing cannabinoids.Terpenylation of olivetol by the pinanes (1S,4S,5S)-(-)-cis-verbenol and (1R,5S,7R)-(+)-cis-chrysanthenol is compared.A major drawback of the latter is partial racemisation which occurs in the verbenone-chrysanthenone isomerisation during its photochemical preparation.Whilst Δ1-THC cannot be directly obtained from verbenol, its tertiary allylic cation permits a much higher yielding terpenylation than the secondary cation from chrysanthenol.
Formation of 1,2-Dioxolanes from Cyclopropanes
Ruecker, Gerhard,Frey, Klaus
, p. 389 - 392 (2007/10/02)
The already known carenols 5 and 7 are obtained by stereoselective oxirane cleavage of (1S,3S,4R,6R)-(+)-3α,4α-epoxycarane (4).Autoxidation of the ketone 8, derived from 7, failed to give any 1,2-dioxolane derivatives. 5 is converted to the hydroperoxide
