92-48-8Relevant articles and documents
Dehydrogenative Carbon-Carbon Bond Formation Using Alkynyloxy Moieties as Hydrogen-Accepting Directing Groups
Minami, Yasunori,Kodama, Tatsuro,Hiyama, Tamejiro
, p. 11813 - 11816 (2015)
In the presence of a catalyst system consisting of Pd(OAc)2, PCy3, and Zn(OAc)2, the reaction of alkynyl aryl ethers with bicycloalkenes, α,ss-unsaturated esters, or heteroarenes results in the site-selective cleavage of two C-H bonds followed by the formation of C-C bonds. In all cases, the alkynyloxy group acts as a directing group for the activation of an ortho C-H bond and as a hydrogen acceptor, thus rendering the use of additives such as an oxidant or base unnecessary. Alkyne into alkene: A palladium catalyst enables dehydrogenative C-C bond-forming reactions between alkynyl aryl ethers and alkenes or heteroarenes. The presence of the alkynyloxy group is key for these transformations as it acts as a directing group for the site-selective cleavage of two C-H bonds as well as an acceptor for the released hydrogen.
Gold(I)-Catalyzed Intramolecular Hydroarylation of Phenol-Derived Propiolates and Certain Related Ethers as a Route to Selectively Functionalized Coumarins and 2 H-Chromenes
Cervi, Aymeric,Vo, Yen,Chai, Christina L. L.,Banwell, Martin G.,Lan, Ping,Willis, Anthony C.
, p. 178 - 198 (2020/12/22)
Methods are reported for the efficient assembly of a series of phenol-derived propiolates, including the parent system 56, and their Au(I)-catalyzed cyclization (intramolecular hydroarylation) to give the corresponding coumarins (e.g., 1). Simple syntheses of natural products such as ayapin (144) and scoparone (145) have been realized by such means, and the first of these subject to single-crystal X-ray analysis. A related process is described for the conversion of propargyl ethers such as 156 into the isomeric 2H-chromene precocene I (159), a naturally occurring inhibitor of juvenile hormone biosynthesis.
Visible-light-induced regioselective alkylation of coumarins via decarboxylative coupling with N-hydroxyphthalimide esters
Jin, Can,Yan, Zhiyang,Sun, Bin,Yang, Jin
supporting information, p. 2064 - 2068 (2019/04/11)
An efficient photocatalytic decarboxylative 3-position alkylation of coumarins by using alkyl N-hydroxyphthalimide esters as alkylation reagents has been developed. A variety of NHP esters derived from aliphatic carboxylic acids (primary, secondary, and tertiary) has been proved to be tolerated for this decarboxylation process, affording a broad scope of 3-alkylated coumarin derivatives in moderate to excellent yields. This protocol was highlighted by its mild conditions, readily available starting materials, operational simplicity, and wide functional group tolerance.
Synthesis method for coumarins compound
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Paragraph 0056; 0057; 0058; 0059; 0060; 0061; 0062; 0063, (2017/08/29)
The invention discloses a synthesis method for a coumarins compound. The structural formula is shown in the specification, wherein R1 is selected from one or more of -H, -CH3, -OCH3, -F, -Cl, -Br, -OH, -NO2 and N(CH2CH3)2 and R2 is selected from one of -H, -CH3 or CH2CH3. According to the invention, a 2-hydroxy cinnamate compound is directly utilized as a raw material and the coumarins compound is synthesized in one step under the catalytic effect of visible light. Compared with the present synthesis method, the synthesis method for the coumarins compound disclosed by the invention has the characteristics of simple method, mild condition and high yield; the reaction is carried out under normal temperature; and the visible light is utilized as a reaction energy source and is green and pollution-free.