22354-39-8Relevant articles and documents
Synthesis of Cyclopentenones through Rhodium-Catalyzed C-H Annulation of Acrylic Acids with Formaldehyde and Malonates
Yu, Shuling,Hong, Chao,Liu, Zhanxiang,Zhang, Yuhong
supporting information, p. 5054 - 5059 (2021/07/20)
An efficient rhodium-catalyzed protocol for the synthesis of cyclopentenones based on a three-component reaction of acrylic acids, formaldehyde, and malonates via vinylic C-H activation is reported. Exploratory studies showed that 5-alkylation of as-prepared cyclopentenones could be realized smoothly by the treatment of a variety of alkyl halides with a Na2CO3/MeOH solution. Excess formaldehyde and malonate led to a multicomponent reaction that afforded the multisubstituted cyclopentenones through a Michael addition.
METHODS OF PREPARING a,?-UNSATURATED OR a-HALO KETONES AND ALDEHYDES
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Paragraph 0087; 0116; 0117; 0120; 0121; 0124-0125, (2017/07/14)
Copper(II) bromide mediated oxidation of acylated enol and use of the reaction in the synthesis of α,β-unsaturated or α-bromo ketones or aldehydes are disclosed. The method provides an efficient and practical process for manufacturing dehydrohedione (DHH) and many other versatile α,β-unsaturated or α-bromo ketones or aldehydes in large scales to avoid using precious metal compounds.
α,β-Unsaturated ketones via copper(II) bromide mediated oxidation
Sharley, James S.,Collado Pérez, Ana María,Ferri, Estela Espinos,Miranda, Amadeo Fernandez,Baxendale, Ian R.
supporting information, p. 2947 - 2954 (2016/05/19)
A protocol for effecting a rapid Saegusa-type oxidation of enol acetates is reported. This new method relies on the in situ elimination of an α-bromo intermediate to generate α,β-unsaturated ketones using copper(II) bromide. The methodology developed was applied to a range of substrates including a cyclohexanone, which could be directly converted to the corresponding phenol derivative. A catalytic system in which a non-masked ketone was successfully oxidised using substoichiometric CuBr2 was also developed as a proof of principle.
Versatile CuI/Pd0 dual catalysis for the synthesis of quaternary α-allylated carbonyl compounds: Development, mechanistic investigations and scope
Nahra, Fady,Mace, Yohan,Boreux, Arnaud,Billard, Francois,Riant, Olivier
, p. 10970 - 10981 (2014/09/17)
We report herein a versatile cooperative dual catalysis reaction based on a CuI/Pd0 system. Mechanistic investigation shows that every component plays a crucial role in determining the reaction outcome. The reaction is successfully extended to various substrates; such as α,β-unsaturated ketones, malonates and coumarins. The strategy tolerates different substitution patterns and affords good yields for each family of substrates.
Copper/palladium-catalyzed 1,4 reduction and asymmetric allylic alkylation of α,β-unsaturated ketones: Enantioselective dual catalysis
Nahra, Fady,Mace, Yohan,Lambin, Dominique,Riant, Olivier
, p. 3208 - 3212 (2013/04/23)
Cooperative efforts: The catalytic coupling of the two organometallic intermediates is possible through a Cu/Pd-based dual catalysis (see scheme; LG=leaving group), in which the CuI catalytic cycle generates catalytically the starting material
Lithium naphthalenide induced reductive selenenylation of α-cyano ketones: A regiocontrolled process for α-phenylseleno ketones and one-pot conversion into enone system
Zhu, Jia-Liang,Ko, Yen-Chun,Kuo, Chun-Wei,Shia, Kak-Shan
, p. 1274 - 1278 (2008/01/08)
An efficient procedure for the regiocontrolled synthesis of α-phenylseleno ketones has been developed, making use of the lithium naphthalenide induced reductive selenenylation of the α-cyano ketone system as a key operation. Moreover, seleno ketones thus generated in situ, upon subsequent treatment with hydrogen peroxide and acetic acid, could be further converted into the corresponding enones with a high degree of regioselectivity, presumably due to the lithium salt mediated selenoxide syn-elimination process. Georg Thieme Verlag Stuttgart.
Rhodium-catalyzed intramolecular hydroacylation of 5- and 6-alkynals: Convenient synthesis of α-alkylidenecycloalkanones and cycloalkenones
Takeishi, Kenzo,Sugishima, Koudai,Sasaki, Kaori,Tanaka, Ken
, p. 5681 - 5688 (2007/10/03)
A novel intramolecular hydroacylation of 5- and 6-alkynals leading to α-alkylidenecycloalkanones was accomplished by using cationic a rhodium(I)/BINAP complex. For all cyclizations described, a single (E)-olefin isomer was obtained. At elevated temperature, hydroacylation and double bond migration of 5- and 6-alkynals proceeded in a one-pot reaction to give cycloalkenones. An intramolecular hydroacylation of a 7-alkynal was unsuccessful. This method represents an attractive new route to highly functionalized α-alkylidenecycloalkanones and cycloalkenones.
A Novel Palladium-Catalyzed Intramolecular Redox Reaction
Hoegenauer, Klemens,Mulzer, Johann
, p. 1495 - 1497 (2007/10/03)
matrix presented A new type of palladium-catalyzed redox reaction is described, forming enones from 2-(2-bromobenzyl)-ketones with an overall loss of HBr. The scope and limitations of the reaction are demonstrated by a series of cyclic and acyclic substra
Strictly regiocontrolled α-monosubstitution of cyclic carbonyl compounds with alkynyl and alkyl groups via Pd-catalyzed coupling of cyclic α-iodoenones with organozincs
Negishi, Ei-Ichi,Tan, Ze,Liou, Show-Yee,Liao, Baiqiao
, p. 10197 - 10207 (2007/10/03)
The conditions for the Pd-catalyzed cross coupling of cyclic α-iodoenones, such as 2-iodo-2-cyclohexenone, with alkynylzincs have been optimized. The use of tris(o-furyl)phosphine (TFP) as a ligand and DMF as a solvent has led to the formation of α-alkynylenones in excellent yields. This optimized procedure has been applied to the synthesis of (±)-harveynone and (±)-tricholomenyn A in high yields. Investigation of related α-alkylation reactions using alkylzincs has revealed the following. Methylzinc and primary alkylzinc derivatives readily undergo Pd-catalyzed cross coupling with α-iodoenones. Although (s-Bu)2Zn also undergoes Pd-catalyzed cross coupling, only the n-Bu-substituted products were obtained, α-Benzylation and α-homobenzylation can proceed satisfactorily, whereas allylzinc and propargylzinc derivatives undergo only addition to the carbonyl group. Although some promising results have been obtained in α-homoallylation and α-homopropargylation, these reactions need to be further improved. (C) 2000 Elsevier Science Ltd.
A Novel Vinyl Anion Equivalent. An Extremely Short Synthesis of 2-Substituted 2-Cycloalkenones and Prostaglandin Key Intermediates via Destannylselenenylation
Kusuda, Shinya,Watanabe, Yoshihiko,Ueno, Yoshio,Toru, Takeshi
, p. 3145 - 3152 (2007/10/02)
The preparation of a novel vinyl anion equivalent and a new destannylselenenylation procedure are described.The conjugate addition of (tributylstannyl)lithium to 2-(phenylseleno)-2-cycloalkenones, followed by the trapping of the resulting enolates with al
