28219-60-5Relevant articles and documents
Mechanically Interlocked Profragrances for the Controlled Release of Scents
Alajarin, Mateo,Berna, Jose,Lopez-Sanchez, Jorge,Pastor, Aurelia
supporting information, p. 15045 - 15054 (2021/10/20)
The synthesis of a series of interlocked profragrances and the study of the controlled release of the corresponding scents are reported. The structures of the profragrances are based on a [2]pseudorotaxane scaffold with a fumaramate thread derived from perfumery alcohols and a tetrabenzylamido ring. The delivery of the scents was accomplished by sequential thermal dethreading and further enzymatic hydrolysis. Alternatively, the dethreading can be achieved by increasing the polarity of the solvent or photochemical isomerization. The temperature of dethreading can be modulated by the steric demand of the ends of the thread, which allows the selection of different precursor structures depending on the desired rates of delivery. The inputs and outputs for the controlled release of the interlocked profragrances correspond to those of YES or AND logic gates.
Transition-metal-catalyzed cyclopropanation of nonactivated alkenes in dibromomethane with triisobutylaluminum
Brunner, Gerhard,Elmer, Susanne,Schroeder, Fridtjof
supporting information; experimental part, p. 4623 - 4633 (2011/10/09)
The cyclopropanation of nonactivated alkenes with inexpensive triisobutylaluminum (TIBA), in dibromomethane as solvent and reagent, is efficiently catalyzed by FeCl3 at ambient temperature. Catalytic amounts of CuI salts, CpTiCl3, and [CpFe(CO) 2]2 are similarly effective. 2-Methylpropane, generated after quench of excess TIBA can be trapped, and excess dibromomethane can be recycled, which makes the method industrially applicable. Solvent-free DIBAH or TIBA reduction of unsaturated carbonyl compounds, followed by in situ TIBA cyclopropanation of the unsaturated aluminum alcoholates in dibromomethane give cyclopropyl alkanols. Dienols such as geraniol, linalool or nor-radjanol are selectively cyclopropanated in their distal position, which allows the synthesis of flavor and fragrance compounds such as δ-citral, cis-javanol, and 7-methyl-georgywood. Uncontrollable exothermic events are avoided due to relatively low reaction temperatures made possible by the catalysts and by the addition mode of the reagents.[1]
METHOD FOR PRODUCING ALKYL-SUBSTITUTED BUTENOLS
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Page 7, (2008/06/13)
Alkyl-substituted butenols having the formula (I): R1-CH2-CH-CR2-CH2OH (I) wherein R1 is a saturated or olefinically unsaturated alkyl or cycloalkyl group having from 4 to 16 carbon atoms and wherein R1 is optionally substituted by an alkyl, cycloalkyl, aryl or alkaryl having up to 12 carbon atoms; R2 is hydrogen or an alkyl group having from 1 to about 6 carbon atoms are produced by a process which comprises: (1) reacting an aldehyde of the formula (II): R1-CH2-CHO (II) wherein R1 has the same meaning as in formula (I), with the corresponding lower aldehyde to form an unsaturated aldehyde in an inert organic solvent; (2) continuously contacting an optionally calcined copper/zinc catalyst with the unsaturated aldehyde under isothermal conditions at temperatures of from about 45 to about 60° C. and under a hydrogen pressure of from 1 to about 300 bar.