56052-83-6Relevant academic research and scientific papers
Raman spectroscopy of unbranched hexenyl methyl ethers containing a terminal methoxy group
Bowen, Richard D.,Edwards, Howell G.M.,Farwell, Dennis W.
, p. 36 - 41 (2010)
The Raman spectra of six isomeric hexenyl methyl ethers in which the alkenyl chain is unbranched and has a terminal methoxy group are reported and discussed. A well-defined and analytically useful correlation is found between the stereochemistry of the double bond and the wavenumber of the ν(C{double bond, long}C) stretching vibration. Confirmation of the stereochemistry of the double bond and its location within the alkyl chain is accessible from the number and wavenumber of the ν(sp2C{single bond}H) stretching bands. In addition, the nature of the double bond in the hexenyl chain is observed to exert an influence on several deformation and skeletal modes. These trends allow the assignment of Raman bands to vibrational modes to be refined or corrected. The implications of this study on model compounds for larger molecules of biological significance in which an alkenyl group is present are considered.
Rh(III)-Catalyzed C-H Activation-Initiated Directed Cyclopropanation of Allylic Alcohols
Phipps, Erik J.T.,Rovis, Tomislav
supporting information, p. 6807 - 6811 (2019/05/10)
We have developed a Rh(III)-catalyzed diastereoselective [2+1] annulation onto allylic alcohols initiated by alkenyl C-H activation of N-enoxyphthalimides to furnish substituted cyclopropyl-ketones. Notably, the traceless oxyphthalimide handle serves three functions: Directing C-H activation, oxidation of Rh(III), and, collectively with the allylic alcohol, in directing cyclopropanation to control diastereoselectivity. Allylic alcohols are shown to be highly reactive olefin coupling partners leading to a directed diastereoselective cyclopropanation reaction, providing products not accessible by other routes.
Entry to β-alkoxyacrylates via gold-catalyzed intermolecular coupling of alkynoates and allylic ethers
Park, Sae Rom,Kim, Cheoljae,Kim, Dong-Gil,Thrimurtulu, Neetipalli,Yeom, Hyun-Suk,Jun, Jungho,Shin, Seunghoon,Rhee, Young Ho
supporting information, p. 1166 - 1169 (2013/05/09)
The first gold-catalyzed intermolecular coupling of alkynoates and allylic ethers invoking alkoxy addition and [3,3]-sigmatropic rearrangement as the key mechanism has been developed. Remarkably, the reaction showed complete chemoselectivity toward the pathway initiated by the alkoxy addition to alkynes. This unprecedented reactivity led to a new access to diversely substituted β-alkoxyacrylates in a highly efficient manner.
Asymmetric allylic alkylation of acyclic allylic ethers with organolithium reagents
Pérez, Manuel,Fa?anás-Mastral, Martín,Hornillos, Valentín,Rudolph, Alena,Bos, Pieter H.,Harutyunyan, Syuzanna R.,Feringa, Ben L.
supporting information, p. 11880 - 11883 (2012/10/29)
A highly efficient, regio- and enantioselective CuI/ phosphoramidite-catalyzed asymmetric allylic alkylation of allyl ethers with organolithium reagents is reported (see scheme). The use of organolithium reagents is essential for this catalytic C-C bond formation due to their compatibility with different Lewis acids. The versatility of allylic ethers under the copper-catalyzed reaction conditions with organolithium reagents is demonstrated in the shortest synthesis of (S)-Arundic acid. Copyright
1-Methoxyhexane-3-thiol, a powerful odorant of clary sage (Salvia sclarea L.)
Van De Waal, Matthijs,Niclass, Yvan,Snowden, Roger L.,Bernardinelli, Geerald,Escher, Sina
, p. 1246 - 1260 (2007/10/03)
The peculiar and highly diffusive odor signal of flowering clary-sage plants (Salvia sclarea L.) was identified to derive from trace amounts of 1 -methoxyhexane-3-thiol (1) by mass-spectrometry analysis and confirmed by comparison with synthetic racemic thiol (±)-1. The enantiomers (S)- and (R)-1 were prepared by enantioselective synthesis, and the absolute configuration of (S)-1 was fully corroborated by X-ray-diffraction analysis of the crystalline thioester (1′S,1S)-2. Compound (S)-1 is one of the most powerful odorants known, with a detection threshold of 0.04·10-3 ng/l air, and is, with its herbaceous-green, alliaceous, and perspiration profile, key to the fragrance of clary-sage flowers and of the freshly distilled essential oil. As a consequence of its unique odor, 1 was also suspected to be part of the volatiles of a Ruta species where it was subsequently identified together with its homologue, 1-methoxyheptane-3-thiol (3), 1-methoxy-4-methylpentane-3-thiol (4), and the known 4-methoxy-2-methylbutane-2-thiol (5). The syntheses of (±)-3 and (±)-4 as well as of the enantiomer (R)-4 are described. In both natural fractions, the ratio (S)-1/(R)-1 was slightly in favor of the (S)-enantiomer. Natural 4 has (R)-configuration.
Origin of the "β-oxygen effect" in the Barton deoxygenation reaction
Crich, David,Beckwith, Athelstan L. J.,Chen, Chen,Yao, Qingwei,Davison, Ian G. E.,Longmore, Robert W.,De Parrodi, Cecilia Anaya,Quintero-Cortes, Leticia,Sandoval-Ramirez, Jésus
, p. 8757 - 8768 (2007/10/02)
Photolysis of O-neopentyl S-tributylstannyl dithiocarbonate with hexaphenyl distannane, and 4-methoxyacetophenone as sensitizer, results in crossover of the stannyl groups. The reaction of O-octyl O′-(2-butoxyethyl) thiocarbonate with tributyltin deuteride or tris(trimethylsilyl)silane and a radical initiator shows no significant preference for the cleavage of either C-O bond. Intermolecular competitions between O-octyl O′-phenyl thiocarbonate and O-(2-butoxyethyl) O′-phenyl thiocarbonate for a deficiency of stannane or silane also indicated no significant preference for reaction of the β-oxygen-substituted substrate, leading to the conclusion that in conformationally unrestricted systems there is no significant β-oxygen effect in the Barton deoxygenation reaction. Competition experiments between the cis- and trans-O-(4-phenylcyclohexyl) S-methyl dithiocarbonates and the cis- and trans-O-(2-phenyl1,3-dioxan-5-yl) S-methyl dithiocarbonates for reaction with tributylstannane reveal that in every case the heterocyclic system is more reactive. The cis-isomers of 4-phenylcyclohexyl S-methyl dithiocarbonate and O-(2-phenyl-1,3-dioxan-5-yl) 5-methyl dithiocarbonate, with their axial xanthates, are more reactive than the corresponding transisomers. Molecular mechanics calculations suggest that the greater reactivity of the cis-series with respect to the trans is due to the greater relief of strain on fragmentation.
Carbonylation of allylic ethers to esters
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, (2008/06/13)
A method is disclosed for the production of esters by reaction of an allylic ether with carbon monoxide in the presence of a catalytically effective amount of a Group VIII noble metal catalyst and halide compound to obtain esters. The halide compound is present in an amount sufficient to prevent the catalyst from being converted into a Group VIII metal during the reaction. When the reaction is conducted in the presence of a quaternary ammonium salt the ester may be extracted by solvent extraction to minimize catalyst decomposition caused when extractive distillation is used to separate the ester.
