B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>: A New Class of Strong and Bulky Lewis Acid for <i>Exo</i>-Selective Intermolecular Diels–Alder Reactions of Unreactive Acyclic Dienes with α,β-Enals
Lewisacid B(C6F5)3 catalyzed the Diels–Alderreactions of multisubstituted open-chain dienes and α,β-enals to afford the desired products with high exo-selectivities are reported. The substituent effect of the dienes and dienophiles on the product’s stereoselectivity was thoroughly investigated, and it was found that most of the desired exo-Diels–Alder products could be obtained in good yields and
据报道,路易斯酸B(C 6 F 5)3催化多取代的开链二烯和α,β-烯醛的Diels-Alder反应,可提供所需的具有高外选择性的产物。彻底研究了二烯和亲二烯体对产物立体选择性的取代作用,发现大多数所需的exo -Diels-Alder产品可以高收率和高exo-立体选择性获得。
Tandem Cyclopropanation with Dibromomethane under Grignard Conditions
In tandem reactions, cyclopropylcarbinols are obtained from allyloxylithium or -magnesium intermediates, generated in situ by alkylation of conjugated aldehydes, ketones, and esters as well as from allyl carboxylates or vinyloxiranes. Using this methodology, numerous fragrance ingredients and their precursors were efficiently converted to the corresponding cyclopropylcarbinols.
Provided is a fragrance composition containing a compound that is highly harmonious with other various fragrances and that can impart a stronger floral feeling by being blended. A fragrance composition containing 3,6-dimethyl-heptane-2-ol. The fragrance composition may further contain at least one selected from the group consisting of, for example, 7-methyloctane-3-ol, esters, carbonates, aldehydes, ethers, lactones, and alcohols other than 3,6-dimethylheptane-2-ol.