6089-04-9Relevant academic research and scientific papers
ω-Alkenylallylboronates: Design, Synthesis, and Application to the Asymmetric Allylation/RCM Tandem Sequence
Barrio, Pablo,Garnes-Portolés, Francisco,Grayson, Matthew N.,Miguélez, Rubén
, p. 3492 - 3495 (2021)
The synthesis of allylboronates bearing an alkenyl moiety appended at a remote position is described for the first time. For that aim, the palladium-catalyzed borylation of the corresponding allylic alcohols was used as the key step. The required allylic alcohols were in turn obtained in 3–4 step sequences. The presence of an extra alkenyl moiety at a strategic position allows the triggering of a tandem asymmetric allylation/RCM reaction sequence that efficiently affords different sized cycles featuring two consecutive stereocenters and an exocyclic alcohol function. Products are obtained in moderate to excellent yields and high enantioselectivities, in most of the cases.
Unsaturated acyclic analogues of 2'-deoxyadenosine and thymidine containing fluorine: Synthesis and biological activity
Xu,Qiu,Chokekijchai,Mitsuya,Zemlicka
, p. 875 - 882 (1995)
The syntheses and biological activities of fluorobutynol 11 and (E)- and (Z)-fluorobutenols 8a,d and 9a,d are described. Alkylation of adenine with bromofluorobutyne 13a afforded intermediate 14 which was converted to fluorobutynol 11. Aldehyde 16a and (c
A novel oxidative cleavage reaction of propargyl alcohol derivatives using K2FeO4-Al2O3
Caddick, Stephen,Murtagh, Lorraine,Weaving, Robert
, p. 3655 - 3656 (1999)
Recent work has shown that a new K2FeO4 based oxidation protocol can promote a highly unusual carbon-carbon bond cleaving reaction of functionalised propargyl alcohols.
Chiral acyl radical equivalents: 5-exo cyclization of conformationally constrained 1,3-dioxolanyl radicals
Stien,Crich,Bertrand
, p. 10779 - 10788 (1998)
Chiral 1,3-dioxolan-2-yl radicals derived from acetals 8 and 9 underwent intramolecular hydrogen abstraction followed by 5-exo-trig cyclization on treatment with tributyltin hydride and AIBN with modest and opposite stereoselectivities. The more highly su
Structure and solvent-induced tuning of laser property and photostability of a boradiazaindacene (BODIPY) dye
Gupta, Monika,Mula, Soumyaditya,Ghanty, Tapan K.,Naik,Ray, Alok K.,Sharma, Anubha,Chattopadhyay, Subrata
, p. 162 - 170 (2017)
Boradiazaindacene (BODIPY) class of laser dyes are highly efficient but degrade rapidly in alcohol solution during lasing action, progressively reducing output power. Photodegradation of these dyes is mainly due to reaction with the in situ generated singlet oxygen (1O2). With the aim to increase the lasing lifetimes of these dyes, we have designed and synthesized a new congener of the widely used BODIPY dye (PM567) by substitution at its B-centre. The new dye was highly fluorescent, and showed comparable lasing efficiency, but better photostability relative to PM567 in both polar (ethanol) and non-polar (1,4-dioxane) solvents, when excited by 2nd harmonic (532 nm) of a pulsed Nd-YAG laser. More interestingly, the lasing efficiency and photostability of both the dyes were much better in 1,4-dioxane than in ethanol. The relative photostabilities of the dyes were rationalized by absorption spectroscopic analyses of their triplet state properties in the respective solvents in the presence of a 1O2 generator or quencher as an additive, pulse radiolysis studies and quantum chemical calculations.
Synthesis and Photoswitching Properties of Bioinspired Dissymmetric I-Pyrone, an Analogue of Cyclocurcumin
Pecourneau, Jérémy,Losantos, Raúl,Monari, Antonio,Parant, Stéphane,Pasc, Andreea,Mourer, Maxime
, p. 8112 - 8126 (2021/06/30)
Cyclocurcumin (CC), a turmeric curcuminoid with potential therapeutic properties, is also a natural photoswitch that may undergo E/Z photoisomerization under UV light. To be further exploited in relevant biological applications, photoactivation under near-infrared (NIR) irradiation is required. Such requirement can be met through opportune chemical modifications, by favoring two-photon absorption (TPA) probability. Herein, a general and efficient synthesis of a biomimetic 2,6-disubstituted-δ-pyrone analogue of CC is described, motivated by the fact that molecular modeling previews an order of magnitude increase of its NIR TPA compared to CC. Three retrosynthetic pathways have been identified (i) via an aryl-oxazole intermediate or via aryl-diynone through (ii) a bottom-up or (iii) a top-down approach. While avoiding the passage through unstable synthons or low-yield intermediate reactions, only the latest approach could conveniently afford the 2,6-disubstituted-I-pyrone analogue of CC, in ten steps and with an overall yield of 18%. The photophysical properties of our biomimetic analogue have also been characterized showing an improved photoisomerization yield over the parent natural compound. The potentially improved nonlinear optical properties, as well as enhanced stability, may be correlated to the enforcement of the planarity of the pyrone moiety leading to a quadrupolar D-π-A-π-D system.
Ni-catalyzed direct carboxylation of propargylic alcohols with carbon dioxide
Yamahira, Tatsuya,Onodera, Gen,Fukuda, Tsutomu,Kimura, Masanari
supporting information, p. 853 - 855 (2021/05/19)
The carboxylation of propargylic alcohols containing a silyl group at the terminal position was conducted in a CO2 atmosphere at atmospheric pressure in the presence of a nickel catalyst and diethylzinc. Here, CO2 was used as not only the C1 source but also the promoter of the COH cleavage processes for the oxidative addition of propargylic alcohols.
Method for synthesizing sex pheromone of hyphantria cunea
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Paragraph 0034-0037, (2021/04/17)
The invention relates to the technical field of hyphantria cunea prevention and treatment, in particular to a synthetic method for synthesizing sex pheromone of hyphantria cunea. According to a traditional method for synthesizing (3Z,6Z,9S,10R)-9,10-epoxy-3,6-heneicosadiene by using propargyl alcohol as a starting material in the traditional technology, various side reactions are liable to occur during a sulfonic acid esterification reaction on a key intermediate (2S,3R)-2,3-epoxy-1-tetradecanol by using trifluoromethanesulfonic anhydride. In order to solve the problems, the (3Z,6Z,9S,10R)-9,10-epoxy-3,6-heneicosadiene is successfully synthesized by taking propargyl alcohol as an initial raw material and taking a Sharpless asymmetric dihydroxylation reaction as a key step without the step of the sulfonic acid esterification reaction on a key intermediate (2S,3R)-2,3-epoxy-1-tetradecanol by trifluoromethanesulfonic anhydride in the preparation process. Therefore, the whole reaction is mild and controllable and few in side reactions, and enantioselectivity is high.
Stereoselective synthesis of C3–C17 and C18–C34 subunits of bullatanocin utilizing α-chloro sulfide intermediates
Chowhan, L. Raju,Raghavan, Sadagopan
supporting information, (2019/09/17)
A convergent synthesis of bullatanocin is envisaged by the union of C18–C34, C3–C17 and the butenolide subunits. The synthesis of the C3–C17 and C18–C34 subunits is disclosed that takes advantage of the chirality of tartaric acid for 1,2-asymmetric induct
Stereochemistry of Linoleic Acid Esters of Hydroxy Linoleic Acids
Wang, Huijing,Kolar, Matthew J.,Chang, Tina,Rizo, José,Konduri, Srihari,McNerlin, Clare,Saghatelian, Alan,Siegel, Dionicio
supporting information, p. 8080 - 8084 (2019/10/14)
The syntheses of linoleic acid esters of hydroxy linoleic acids (LAHLAs) present in oat oil and human serum have been achieved, providing access to material for testing and the determination of the stereochemistry of the natural compounds. While 9- and 13-LAHLAs were found to be a mixture of enantiomers 15-LAHLA is generated in a single optical form in oat oil. The stereochemistry of 15-LAHLA in oat oil was found to be opposite to that reported for digalactosyldiacylglycerol that possesses an embedded 15-LAHLA.
