4017-88-3Relevant academic research and scientific papers
Some unusual transformations of a highly reactive α-bromocaranone
Samkian, Adrian E.,Sercel, Zachary P.,Virgil, Scott C.,Stoltz, Brian M.
supporting information, (2022/01/04)
The facile synthesis of a highly reactive α-bromocaranone from (+)-carene is reported. This intermediate was found to generate diverse chiral building blocks through radical or carbocation mediated cyclopropyl fragmentation reactions in moderate to excellent yields. Furthermore, the formation of an unexpected carvone derivative prompted several control studies that provided mechanistic insight into an unusual transformation. This study not only demonstrates the synthesis of a variety of chiral building blocks but provides insight into the reactivity of keto-halo-cyclopropanes in general.
A non-dissociative open-flask hydroboration with ammonia borane: Ready synthesis of ammonia-trialkylboranes and aminodialkylboranes
Ramachandran, P. Veeraraghavan,Drolet, Michael P.,Kulkarni, Ameya S.
supporting information, p. 11897 - 11900 (2016/10/09)
Under open-flask conditions, ammonia borane hydroborates olefins in refluxing tetrahydrofuran. Unlike conventional hydroboration, the Lewis base (ammonia) is not dissociated from the boron center. Terminal alkenes selectively provide ammonia-trialkylborane complexes. On the other hand, internal alkenes afford aminodialkylboranes via a metal-free hydroboration-dehydrogenation sequence. Alkaline hydrogen peroxide oxidation of the products provides the corresponding alcohols in high yields.
Chemical and microbiological oxidation of (-)-cis-carane-4-one leading to chiral compounds and evaluation of their antifeedant activity
Wincza, Ewelina,Lochynski, Stanislaw
, p. 196 - 203 (2013/09/24)
Starting from (+)-3-carene 1, naturally occurring bicyclic, monoterpene hydrocarbon, (-)-cis- carane-4-one 3 was obtained as a result of the two-step synthesis. Our investigations were focused on the optimization of chemical Baeyer-Villiger reaction of 3 leading to a-lactones. A mixture of terpenoid lactones 4a, 4b was obtained and next separated using column chromatography. The pure compounds were subjected to the evaluation of antifeedant activity towards three species of storage insects. Fusarium culmorum, Fusarium oxysporum and Aspergillus niger were chosen among six fungal strains to perform microbiological Baeyer- Villiger oxidation. As a result, three derivatives were isolated and characterized by spectroscopic methods. ARKAT-USA, Inc.
Catalytic transformations of 3-carene oxide over alumina-rare earth oxide catalysts
Jayasree, J.,Narayanan, C. S.
, p. 577 - 580 (2007/10/02)
Isomerization of 3-carene oxide over binary oxide catalysts like Al2O3-Y2O3, Al2O3-Sm2O3, Al2O3-Eu2O3, Al2O3-Pr6O11 and Al2O3-Nd2O3 at 80 deg C and 110 deg C has been studied. 3,6,6-Trimethylbicyclohexane-3-carboxaldehyde and caranone are the major products formed at 80 deg C.Rise in reaction temperature results in an increase in epoxide transformation and an irregular variation in the yield of products.
Novel Reduction of Carboxylic Acids and Hydroboration of Olefins by Electrolysis of Sodium Borohydride
Shundo, Ryushi,Matsubara, Yoshiharu,Nishiguchi, Ikuzo,Hirashima, Tsuneaki
, p. 530 - 534 (2007/10/02)
Electrochemical oxidation of sodium borohydride in diglyme containing aliphatic or aromatic carboxylic acids followed by acid-catalyzed hydrolysis afforded the corresponding primary alcohols in good yields.Furthermore, similar electrochemical oxidation in the presence of a variety of olefins instead of carboxylic acids, followed by treatment with alkaline-hydrogen peroxide, brought about novel electrochemical hydroboration to give the corresponding alcohols regio- and stereoselectively in good yields.
Synthesis of Some 4-Cyanocaranes
Fringuelli, F.,Minuti, L.,Taticchi, A.
, p. 1497 - 1510 (2007/10/02)
Four optically active 4-cyanocaranes diastereoisomers have been synthesized starting from (+)-car-3-ene and their structures supported by chemical evidences and X-ray analysis.
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.
Novel Method for Hydroboration of Olefins Using Electrolysis
Shundo, Ryushi,Matsubara, Yoshiharu,Nishiguchi, Ikuzo,Hirashima, Tsuneaki
, p. 2033 - 2036 (2007/10/02)
A first example of electrochemical hydroboration of olefins was found.Anodic oxidation of sodium borohydride in the presence of olefins in diglyme followed by conventional oxidation gave the corresponding alcohols regio- and stereoselectively in good yields.
LIGHT-MEDIATED TRANSFORMATIONS OF OLEFINS INTO ALCOHOLS: REACTIONS OF HYDROXYL RADICALS WITH CYCLOALKENES
Sonawane, H. R.,Nanjundiah, B. S.,Kelkar, R. G.
, p. 6673 - 6682 (2007/10/02)
Reactions of hydroxyl radicals, generated by photodecomposition of hydrogen peroxide in acetonitrile, with a wide variety of cycloalkenes have been examined.The results show that the major reaction is the addition of hydroxyl radicals to the less substituted end of the double bond, furnishing the secondary alcohols.The reactivity pattern and the observed regio- and stereoselectivity clearly reveal that the steric parameters associated with the substrates play a dominant role in directing the addition reactions.More importantly, this study led to the development of a new methodology for the facile conversions of olefins essentially into secondary alcohols, and includes a few examples which demonstrate the potential of the method.
Studies on the Terpenoids and Related Alicyclic Compounds. XXXII. A Synthesis of Chiral Dimethylcyclopropane Derivatives, Versatile Chiral Synthons for Casbane, Lathyrane, and Ingenane-Type Diterpenoids, from (+)-3-Carene
Satoh, Tsuyoshi,Okuda, Teruyoshi,Kaneko, Youhei,Yamakawa, Koji
, p. 1401 - 1410 (2007/10/02)
A synthesis of chiral dimethylcyclopropane derivatives, useful for the synthesis of casbane, lathyrane, and ingenane-type diterpenoids, from easily available (+)-3-carene is described.The silyl enol ether (8) was derived from (-)-cis-4-caranone (7b), which was obtained from (+)-3-carene (6).Ozonolysis of 8 gave 9a and 10.The right half segment (11b) for a synthesis of crotonitenone (3) was formed from 9a in three steps.The epoxide (12) was isomerized to a mixture of the allylic alcohols (13a) and (14a), which was transformed to the ketone (20) in five steps.Methylation of 20 followed by phosphorylation and reduction gave (+)-cis-4-caranone (23) in about 40 percent overall yield from 12.The methylester (+)-(32b) and its enantiomer (-)-(34b) were synthesized from (+)-6.Ozonolysis of a mixture of the silyl enol ether (30) and (31) followed by methylation with diazomethane gave 32a, which was hydrolyzed to give the desired (+)-32b.The enantiomer (-)-34b was derived from 32a in five steps.
