6994-89-4Relevant academic research and scientific papers
Preparation of ketones from esters via substituted cyclopropanols. Application to the synthesis of (±)-ipsenol, (±)-ipsdienol and amitinol, the components of aggregation pheromones of the Ips bark beetles
Chevtchouk, Timour A.,Isakov, Vladimir E.,Kulinkovich, Oleg G.
, p. 13205 - 13210 (1999)
The regioselective two-step sequence of bromination- dehydrobromination of 2-(2,2-diethoxy)-1-methyl-1-cyclopropanol affords 3-(2,2-diethoxyethyl)-3-buten-2-one in high yield. The reduction of the latter, followed by chlorination and dehydrochlorinatiou, provides 2-(2,2-diethoxyethyl)-1,3-butadiene that was used as a building block for the synthesis of (±)- ipsenol, (±)ipsdienol and amitinol - the components of aggregation pheromones of the Ips bark beetles.
Carboindation of Alkynes. Regio- and Stereoselective Allylation of Carbon-Carbon Triple Bonds of Alkynols by Allylic Indium Reagents
Araki, Shuki,Imai, Akira,Shimizu, Ken,Yamada, Masafumi,Mori, Akihiro,Butsugan, Yasuo
, p. 1841 - 1847 (2007/10/02)
Allylindium sesquihalides undergo smooth allylindation with terminal alkynes bearing a neighboring hydroxyl group at 100-140 deg C to give allylalkenols.The coupling occurred regioselectively at the γ-carbon of the allylindium reagents via syn-addition, whereas the regioselectivity concerning the alkynol depends upon the structures of both allylindium and alkynol.The allylation of nonfunctionalized alkynes is less efficient, requiring higher reaction temperature (150-180 deg C) and giving lower yields.Mechanistic considerations suggest a hydroxyl-assisted concerted process for the allylindation of alkynols, whereas a radical pathway is more likely for nonfunctionalized alkynes.Three monoterpene alcohols, i.e., yomogi alcohol, achillenol, and isomyrcenol, were conveniently prepared via allylindation of appropriate alkynols.
A Synthesis of trans-β-Farnesene from Myrcene which Includes a Modified Work up Method for Dibah Reductions of Esters to Aldehydes
Baeckstroem, Peter,Li, Lanna,Wickramaratne, Mahinda,Norin,Torbjoern
, p. 423 - 429 (2007/10/02)
A simple synthesis of trans-β-farnesene, an alarm pheromone for aphids, from myrcene is described and a reliable procedure for working up of DIBAH reduction from esters to aldehydes is introduced.
PALLADIUM CATALYZED COUPLING OF ORGANOSTANNANES WITH VINYL EPOXIDES
Tueting, David R.,Echavarren, Antonio M.,Stille, J. K.
, p. 979 - 992 (2007/10/02)
The coupling reaction of organotin reagents with vinyl epoxides, catalyzed by palladium, takes place at ambient temperatures, regioselectively, giving predominately the 1,4-addition product.Both aryl- and vinylstannanes undergo coupling in high yields, wh
Photooxidation with Simultaneous Reduction of Hydroperoxides with Tetrabutylammonium Borohydride. Synthesis of Perillenal from Myrcene
Baeckstroem, P.,Okecha, S.,Silva, N. de,Wijekoon, D.,Norin, T.
, p. 31 - 36 (2007/10/02)
The synthetic routes to 2-methyl-5-(3-furyl)-2-pentenal, perillenal (1), starting from 2-methyl-6-methylene-2,7-octadiene, myrcene (2), are described.Myrcene (2) was either photooxidized to a mixture of the allylic alcohols 3 and 4 or converted to the aldehyde 11 by oxidation with selenium dioxide followed by chromium trioxide dipyridine in acetic acid.The alcohols 3 and 4 and the aldehyde 11 were cyclized with singlet oxygen to the endoperoxides 5, 6, and 12, respectively.The endoperoxides were converted to the furans 7, 8, and 1 by treatment with Fe(II).The secondary allylic furan 8 was converted to perillenal (1) by a one-step reaction involving an allylic rearrangement and an oxidation with pyridinium chlorochromate in the presence of p-toluenesulfonic acid in dichloromethane.A method for photooxidation and simultaneous reduction of hydroperoxides with tetrabutylammonium borohydride is presented.
