67845-50-5Relevant academic research and scientific papers
Synthesis of (S)- and (R)-sporochnol by using the allylic substitution of the secondary allylic picolinate
Kobayashi, Yuichi,Sugihara, Yusuke,Tojo, Toshifumi,Ozaki, Takuri
, p. 47 - 54 (2017/03/14)
The allylic substitution of secondary allylic picolinates and copper reagents for the construction of a quaternary carbon was applied to synthesis of sporochnol. The enantiomerically enriched allylic picolinate (R)-5 was synthesized through the asymmetric hydrogen transfer of acetylene ketone 11 and the Pd-catalyzed methylation of the iodoallylic alcohol 16a. The key allylic substitution of the allylic picolinate (R)-5 with 4-MeOC6H4MgBr/Cu(acac)2 (2:1) proceeded with 95% chirality transfer with 98% regioselectivity to afford anti SN2' product 6 in 89% yield, which was converted to the methyl ether of unnatural (R)-sporochnol. Similarly, the methyl ether of (S)-sporochnol (the natural form) was synthesized.
Perfume systems
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Page/Page column 29, (2016/09/28)
The present application relates to perfume delivery systems and consumer products comprising perfume delivery systems and or perfume raw materials, as well as processes for making and using such perfume delivery systems and consumer products.
Allylic substitution for construction of a chiral quaternary carbon possessing an aryl group
Feng, Chao,Kobayashi, Yuichi
, p. 3755 - 3766 (2013/06/05)
Phenylcopper reagents derived from 2:1 PhMgBr/Cu(acac)2 and 3:1:1 PhMgBr/Cu(acac)2/ZnI2 were found to be highly reactive and regioselective in the allylic substitution of γ,γ- disubstituted secondary allylic picolinates designed for construction of a quaternary carbon, whereas the previous 2:1 ArMgBr/CuBr·Me2S reagent and that with ZnX2 were unsuccessful. The generality of the ArMgBr/Cu(acac)2 reagent was examined with enantiomerically enriched allylic picolinates, which furnished quaternary carbons with high efficiency in >92% regioselectivity and >97% chirality transfer. Two cyclohexanes with a quaternary carbon were synthesized by using these reagents.
NOVEL ORGANOLEPTIC COMPOUNDS
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Paragraph 0056, (2013/07/31)
The present invention relates to novel compounds and their use in an olfactory acceptable amount in perfume compositions as flavor and/or fragrance enhancing agents and to methods of improving, enhancing or modifying a fragrance formulation comprising adding to a consumer composition an olfactory acceptable amount of any one or more of the novel compounds.
Highly stereoselective C-C bond formation by rhodium-catalyzed tandem ylide formation/[2,3]-sigmatropic rearrangement between donor/acceptor carbenoids and chiral allylic alcohols
Li, Zhanjie,Parr, Brendan T.,Davies, Huw M. L.
, p. 10942 - 10946 (2012/08/07)
The tandem ylide formation/[2,3]-sigmatropic rearrangement between donor/acceptor rhodium carbenoids and chiral allyl alcohols is a convergent C-C bond forming process, which generates two vicinal stereogenic centers. Any of the four possible stereoisomers can be selectively synthesized by appropriate combination of the chiral catalyst Rh2(DOSP)4 and the chiral alcohol.
Fine-tuning catalytic activity and selectivity-[Rh(amino acid thioamide)] complexes for efficient ketone reduction
Ahlford, Katrin,Livendahl, Madeleine,Adolfsson, Hans
supporting information; experimental part, p. 6321 - 6324 (2010/02/28)
Amino acid-derived thioamides are prepared and evaluated as ligands in the rhodium-catalyzed asymmetric transfer hydrogenation of ketones in 2-propanol. It is found that increasing the steric bulk at the C-terminus of the ligand had a positive impact on both activity and selectivity in the reduction reaction. In order to find the optimum catalyst, a study is performed on a series of thioamide ligands having substituents of varying size.
Photochemical Reactions Photochemistry of Acylsilanes: Photolyses and Thermolyses of α,β-Epoxy Silyl Ketones
Scheller, Markus E.,Frei, Bruno
, p. 69 - 78 (2007/10/02)
The photolyses and thermolyses of the α,β-epoxy silyl ketones 5 and 6 are described.On n,?*-excitation, the silyl ketones 5 and 6 were transformed to the ketone 7 and the ketene 8 in quantitative yield.The formation of 8 may be explained by initial cleavage of the C(α)-O bond and subsequent C(1) -> C(2) migration of the (t-Bu)Me2Si group.In contrast to the acylsilanes 5 and 6, the photolyses of the analogous methyl ketones 11 and 12 gave a very complex mixture of products.On thermolysis, 5 and 6 yielded the ketone 7 and the acetylenic compound 9, which were probably formed via a siloxycarbene intermediate.In addition, the 1,3- dioxole 10 was formed via an initial C(α)-C(β) bond cleavage leading to the ylide g and subsequent intramolecular addition of the carbonyl group.The analogous 1,3-dioxole 13 was obtained on pyrolysis of the methyl ketones 11 and 12.
Me5Cu3Li2: A Reagent for Conjugate Methylation of α,β-Unsaturated Aldehydes
Clive, Derrick L.J.,Farina, Vittorio,Beaulieu, Pierre L.
, p. 2572 - 2582 (2007/10/02)
Me5Cu3Li2, in ether or ether-pentane mixtures, converts α,β-unsaturated aldehydes efficiently into β-methyl aldehydes.In many cases of synthetic interest the amount of 1,2-methylation is negligible, and the reagent is far superior to Me2CuLi for conjugate methylation of enals.The performance of Me5Cu3Li2 is poor in sterically demanding situations, however.Several cuprate species were evaluated but none works as well as Me5Cu3Li2.For example, citral undergoes conjugate methylation with Me5Cu3Li2 in 80percent yield, and the product contains less than 0.5percent of 1,2-adduct.With Me2CuLi the product contains 10percent of 1,2-adduct.
Conjugate Addition of Methyl Groups to αβ-Unsaturated Aldehydes: Use of Me5Cu3Li2
Clive, Derrick L. J.,Farina, Vittorio,Beaulieu, Pierre
, p. 643 - 644 (2007/10/02)
Me5Cu3Li2 converts αβ-unsaturated aldehydes efficiently into β-methyl aldehydes and, unlike Me2CuLi, it usually gives a negligible amount of the 1,2-adduct even when a quaternary carbon is generated in the reaction.
ACTION DES DIALKYLCUPRATES DE LITHIUM SUR LES ALDEHYDES α,β-ETHYLENIQUES
Chuit, C.,Foulon, J. P.,Normant, J. F.
, p. 2305 - 2310 (2007/10/02)
Nearly exclusive 1-4 addition products are obtained by action of lithium dialkylcuprates with α,β-ethylenic aldehydes.Non polar solvents and low temperatures favor this reaction.Only α,β-ethylenic aldehydes having a trisubstituted double bond give a relatively important proportion of 1-2 addition product.
