- Ynonylation of Acyl Radicals by Electroinduced Homolysis of 4-Acyl-1,4-dihydropyridines
-
Herein we report the conversion of 4-Acyl-1,4-dihydropyridines (DHPs) into ynones under electrochemical conditions. The reaction proceeds via the homolysis of acyl-DHP under electron activation. The resulting acyl radicals react with hypervalent iodine(III) reagents to form the target ynones or ynamides in acceptable yields. This mild reaction condition allows wider functionality tolerance that includes halides, carboxylates, or alkenes. The synthetic utility of this methodology is further demonstrated by the late-stage modification of complex molecules.
- Luo, Xiaosheng,Wang, Ping
-
supporting information
p. 4960 - 4965
(2021/07/20)
-
- Enantioselective Rh(II)-Catalyzed Desymmetric Cycloisomerization of Diynes: Constructing Furan-Fused Dihydropiperidines with an Alkyne-Substituted Aza-Quaternary Stereocenter
-
Described herein is an enantioselective dirhodium(II)-catalyzed cycloisomerization of diynes achieved by the strategy of desymmetrization, which not only represents a new cycloisomerization reaction of diynes but also constitutes the first Rh(II)-catalyzed asymmetric intramolecular cycloisomerization of 1,6-diynes. This protocol provides a range of valuable furan-fused dihydropiperidine derivatives with an enantiomerically enriched alkynyl-substituted aza-quaternary stereocenter in high efficiency, complete atom economy, and excellent enantioselectivity (up to 98% ee). Besides, the highly functionalized products could be easily transformed into various synthetically useful building blocks and conjugated with a series of pharmaceutical molecules. The mechanism involving a concerted [3+2] cycloaddition/[1,2]-H shift of the Rh(II) carbenoid intermediate was elucidated by DFT calculations and mechanistic studies. More importantly, the first single crystal of alkyne-dirhodium(II) was obtained to show that a η2-coordinating activation of alkynal by dirhodium(II) was involved. Weak hydrogen bondings between the carboxylate ligands and alkynal were found, which probably made the well-defined paddlewheel-like dirhodium(II) distinctive from other metal complexes in catalyzing this transformation. Furthermore, the origin of the enantioselectivity was elucidated by a Rh2(R-PTAD)4-alkyne complex and additional calculational studies.
- Cao, Tongxiang,Chen, Kai,Lu, Jiajun,Ma, Jun,Wu, Rui,Zhu, Shifa
-
supporting information
p. 14916 - 14925
(2021/09/18)
-
- Alkyne derivative as well as preparation method and application thereof (by machine translation)
-
The invention belongs to the technical field of organic synthesis, and discloses an acetylenic ketone derivative and a preparation method and application thereof. The formula (I) is shown in the structural formula of the alkyne derivative. R1 And R2 Heterocyclyl groups of C1 - C20, halogen, ester, carbonyl, nitro, substituted amino, C5 - C30, or C5 - C30, respectively. To the strategy of nickel catalytic reduction coupling, a carboxylic acid derivative which is widely used in nature is used as a substrate, an alkyne halide is combined as an active alkynylation reagent, and under the condition of room temperature, the universality and the high efficiency method for rapidly constructing various substituted alkynes are obtained. The alkyne compound disclosed by the invention not only can be used as a practical synthesis, but also can be used as a precursor of heterocyclic compounds such as furan, pyrazole, quinoline, pyrimidine and the like. (by machine translation)
- -
-
Paragraph 0067-0072
(2020/06/05)
-
- Acyl Radicals from Benzothiazolines: Synthons for Alkylation, Alkenylation, and Alkynylation Reactions
-
We describe herein a fundamentally new visible light-driven homolytic C-C bond breaking mode for the generation of acyl radicals from C2-acyl-substituted benzothiazolines. The reactive species can be used as versatile synthons for formal radical alkylatio
- Li, Lei,Guo, Shan,Wang, Qi,Zhu, Jin
-
p. 5462 - 5466
(2019/08/01)
-
- Alkynylation of Csp2 (O)–H Bonds Enabled by Photoredox-Mediated Hydrogen-Atom Transfer
-
The development of new hydrogen-atom transfer (HAT) strategies within the framework of photoredox catalysis is highly appealing for its power to activate a desired C?H bond in the substrate leading to its selective functionalization. Reported here is the first photoredox-mediated hydrogen-atom transfer method for the efficient synthesis of ynones, ynamides, and ynoates with high regio- and chemoselectivity by direct functionalization of Csp2 (O)?H bonds. The broad synthetic application of this method has been demonstrated by the selective functionalization of C(O)?H bonds within complex molecular scaffolds.
- Mukherjee, Satobhisha,Garza-Sanchez, R. Aleyda,Tlahuext-Aca, Adrian,Glorius, Frank
-
supporting information
p. 14723 - 14726
(2017/10/18)
-
- PHOSPHINE COMPOUND HAVING PERFLUORO GROUP, AND COMPLEX BETWEEN METAL AND PHOSPHINE HAVING PERFLUORO GROUP
-
PROBLEM TO BE SOLVED: To provide a perfluoroalkylphosphine compound, and a complex between a metal and the perfluoroalkylphosphine. SOLUTION: A perfluoroalkylphosphine compound is a phosphine compound represented by the general formula Rf-PR1R2. In the formula, R1 and R2 are each independently a substituted or unsubstituted hydrocarbon group; Rf is a perfluorinated hydrocarbon group. Also provided is a complex between the perfluoroalkylphosphine and a phosphine coordination metal. SELECTED DRAWING: None COPYRIGHT: (C)2016,JPOandINPIT
- -
-
Paragraph 0275; 0280-0282; 0285
(2018/10/16)
-
- METHODS OF PRODUCING PHOSPHINE COMPOUND HAVING PERFLUORO GROUP AND COMPLEX BETWEEN METAL AND PHOSPHINE HAVING PERFLUORO GROUP
-
PROBLEM TO BE SOLVED: To provide methods of producing a perfluoroalkylphosphine compound improved in a phosphorus element yield and a chemical yield. SOLUTION: A method of producing a perfluoroalkylphosphine compound comprises either reacting a perfluoroalkyl iodide with, e.g., 2,4,6-trimethylbenzoyldiphenylphosphine oxide (TMDPO) or a triarylphosphine such as triphenylphosphine, which are easily available, in the presence of a radical generator such as azobis(isobutyronitrile) or light irradiation, or reacting TMDPO or the like with perfluoroalkyl iodide in the presence of diphenylphosphine, diethylphosphine, dicyclohexylphosphine or the like. SELECTED DRAWING: None COPYRIGHT: (C)2016,JPOandINPIT
- -
-
Paragraph 0233-0234; 0238
(2018/10/19)
-
- Radical-induced metal-free alkynylation of aldehydes by direct C-H activation
-
A direct C(sp2)-H alkynylation of aldehyde C(O)-H bonds with hypervalent iodine alkynylation reagents provides ynones under metal-free conditions. In this method, 1-[(triisopropylsilyl)ethynyl]-1,2-benziodoxol-3(1H)-one (TIPS-EBX) constitutes a
- Liu, Xuesong,Yu, Linqian,Luo, Mupeng,Zhu, Jidong,Wei, Wanguo
-
supporting information
p. 8745 - 8749
(2015/06/08)
-
- Metal-free synthesis of ynones via direct C-H alkynylation of aldehydes with ethynylbenziodoxolones
-
Abstract A metal-free synthesis of ynones via direct alkynlyation of C-H bonds in aldehydes with ethynylbenziodoxolones is described. A variety of unactivated aldehydes undergo this transformation, affording ynones in good yields. These ynones could be fu
- Zhang, Ruo-Yi,Xi, Long-Yi,Zhang, Lei,Chen, Shan-Yong,Yu, Xiao-Qi
-
supporting information
p. 6176 - 6182
(2015/08/03)
-
- Metal-free carbonyl C(sp2)-H oxidative alkynylation of aldehydes using hypervalent iodine reagents leading to ynones
-
A new metal-free tert-butyl hydroperoxide (TBHP)-mediated carbonyl C(sp2)-H oxidative alkynylation of aldehydes with ethynyl benziodoxolones (EBX) for the synthesis of ynones is described. This method is based on a carbonyl C(sp2)-H
- Ouyang, Xuan-Hui,Song, Ren-Jie,Wang, Cheng-Yong,Yang, Yuan,Li, Jin-Heng
-
supporting information
p. 14497 - 14500
(2015/09/28)
-
- Transition-Metal-Free Synthesis of Ynones via Decarboxylative Alkynylation of α-Keto Acids under Mild Conditions
-
A transition-metal-free synthetic method of various ynones via decarboxylative alkynylation of α-keto acids is described. The reaction is carried out under mild conditions and exhibits remarkable tolerance of functional groups. The mechanism of a radical
- Wang, Peng-Fei,Feng, Yi-Si,Cheng, Zhi-Fei,Wu, Qiu-Min,Wang, Guang-Yu,Liu, Liang-Liang,Dai, Jian-Jun,Xu, Jun,Xu, Hua-Jian
-
p. 9314 - 9320
(2015/09/28)
-
- Decarboxylative Alkynylation of α-Keto Acids and Oxamic Acids in Aqueous Media
-
A mild K2S2O8 promoted decarboxylative alkynylation of α-keto acids and oxamic acids has been developed. This process features mild reaction conditions, a broad substrate scope, and good functional-group tolerance, therefo
- Wang, Hua,Guo, Li-Na,Wang, Shun,Duan, Xin-Hua
-
supporting information
p. 3054 - 3057
(2015/06/30)
-
- Dual Hypervalent Iodine(III) Reagents and Photoredox Catalysis Enable Decarboxylative Ynonylation under Mild Conditions
-
A combination of hypervalent iodine(III) reagents (HIR) and photoredox catalysis with visible light has enabled chemoselective decarboxylative ynonylation to construct ynones, ynamides, and ynoates. This ynonylation occurs effectively under mild reaction conditions at room temperature and on substrates with various sensitive and reactive functional groups. The reaction represents the first HIR/photoredox dual catalysis to form acyl radicals from α-ketoacids, followed by an unprecedented acyl radical addition to HIR-bound alkynes. Its efficient construction of an mGlu5 receptor inhibitor under neutral aqueous conditions suggests future visible-light-induced biological applications.
- Huang, Hanchu,Zhang, Guojin,Chen, Yiyun
-
supporting information
p. 7872 - 7876
(2015/06/30)
-
- Photoinduced Synthesis of P-Perfluoroalkylated Phosphines from Triarylphosphines and Their Application in the Copper-Free Cross-Coupling of Acid Chlorides and Terminal Alkynes
-
A practical synthesis yielding P-perfluoroalkylated phosphines from triarylphosphines and perfluoroalkyl iodides has been developed. The photoinduced reaction involves the substitution of aryl groups on the phosphorus atom with perfluoroalkyl groups to successfully afford P-perfluoroalkylated phosphines. In addition, the P-perfluoroalkylated phosphines were found to promote the Cu-free cross-coupling reaction of acid chlorides with terminal alkynes.
- Kawaguchi, Shin-Ichi,Minamida, Yoshiaki,Okuda, Takumi,Sato, Yuki,Saeki, Tomokazu,Yoshimura, Aya,Nomoto, Akihiro,Ogawa, Akiya
-
p. 2509 - 2519
(2015/08/18)
-
- Developing asymmetric iron and ruthenium-based cyclone complexes; Complex factors influence the asymmetric induction in the transfer hydrogenation of ketones
-
The preparation of a range of asymmetric iron and ruthenium-cyclone complexes, and their application to the asymmetric reduction of a ketone, are described. The enantioselectivity of ketone reduction is influenced by a single chiral centre in the catalyst, as well as by the planar chirality in the catalyst. This represents the first example of asymmetric ketone reduction using an iron cyclone catalyst.
- Hopewell, Jonathan P.,Martins, Jose E. D.,Johnson, Tarn C.,Godfrey, Jamie,Wills, Martin
-
supporting information; experimental part
p. 134 - 145
(2012/01/12)
-
- An efficient and high-yielding one-pot synthesis of 4-acyl-1,2,3-triazoles via triisopropylsilyl-protected ynones
-
A practical and efficient process has been developed for the synthesis of 1-substituted 4-acyl-1H-1,2,3-triazoles using a three-step one-pot synthetic approach. This transformation involves an initial preparation of triisopropylsilyl (TIPS)-protected ynon
- Hwang, Soonho,Bae, Hoon,Kim, Sanghee,Kim, Sumin
-
experimental part
p. 1460 - 1465
(2012/03/08)
-
- Pd-catalyzed coupling reaction of acid chlorides with terminal alkynes using 1-(2-pyridylethynyl)-2-(2-thienylethynyl)benzene ligand
-
In the presence of 1-(2-pyridylethynyl)-2-(2-thienylethynyl)benzene as a ligand, the direct synthesis of alkynones has accomplished by a Pd-catalyzed coupling reaction of acid chlorides with terminal acetylenes under mild conditions.
- Atobe, Shingo,Masuno, Haruna,Sonoda, Motohiro,Suzuki, Yuki,Shinohara, Hiroyuki,Shibata, Satoshi,Ogawa, Akiya
-
supporting information; experimental part
p. 1764 - 1767
(2012/05/04)
-
- 1,4-Dialkynylbutatrienes: Synthesis, stability, and perspectives in the chemistry of carbo-benzenes
-
The π-electron-rich C8-conjugated sequence of 1,4-dialkynylbutatrienes is identified as a fragile and fascinating motif occurring in carbo-benzene derivatives, and in Diederich's 1,4-bis(arylethynyl)- or 1,4-bis(triisopropylsilylethynyl)butatriene "capped" representatives, in particular, in tetraalkynylbutatriene. The family of symmetrical 1,4-dialkynylbutatrienes (E-C≡C)RC=C=C=CR(C≡C-E) is extended to functional caps (E=H, CH3, C≡CPh, CPh=CHBr, or CPh=CBr2) with non-alkynyl substituents at the sp2 vertices (R=Ph or CF3). The targets were selected for their potential in appealing retrosynthetic routes to carbo-benzenes, in which the aromatic C18 macrocycle would be directly generated by sequential metathesis or reductive coupling processes. The functional 1,4-dialkynylbutrienes were synthesized by either classical methods used for the preparation of generic butatrienes (R′Li/CuX-mediated reductive coupling of gem-dihaloenynes or SnCl2/HCl-mediated reduction of 3,6-dioxy-octa-1,4,7-triyne precursors). Their spectroscopic and electrochemical properties are compared and analyzed on the basis of the relative extent of total conjugation.
- Maraval, Valerie,Leroyer, Leo,Harano, Aya,Barthes, Cecile,Saquet, Alix,Duhayon, Carine,Shinmyozu, Teruo,Chauvin, Remi
-
supporting information; experimental part
p. 5086 - 5100
(2011/06/09)
-
- Fast oxy-cope rearrangements of bis-alkynes: Competition with central C-C bond fragmentation and incorporation in tunable cascades diverging from a common bis-allenic intermediate
-
Fast anionic oxy-Cope rearrangements of 1,5-hexadiyn-3,4-olates can be incorporated into cascade transformations which rapidly assemble densely functionalized cyclobutenes or cyclopentenones via a common bis-allenic intermediate. The competition between f
- Pal, Runa,Clark, Ronald J.,Manoharan, Mariappan,Alabugin, Igor V.
-
supporting information; experimental part
p. 8689 - 8692
(2011/03/19)
-
- Synthesis of isoxazoles via electrophilic cyclization
-
(Chemical Equation Presented) A variety of 3,5-disubstituted 4-halo(seleno)isoxazoles are readily prepared in good to excellent yields under mild reaction conditions by the reaction of 2-alkyn-1-one O-methyl oximes with ICI, I2, Br2,
- Waldo, Jesse P.,Larock, Richard C.
-
p. 5203 - 5205
(2007/10/03)
-
- Synthesis of Ynones by Palladium-Catalyzed Acylation of Terminal Alkynes with Acid Chlorides
-
Phosphane-free oxime-derived palladacycle 2 is an efficient precatalyst for the copper-free acylation of terminal alkynes with different carboxylic acid chlorides in toluene in the presence of 3 equiv of TEA as base, giving the corresponding ynones in goo
- Alonso, Diego A.,Najera, Carmen,Pacheco, Ma Carmen
-
p. 1615 - 1619
(2007/10/03)
-
- An extremely facile aza-Bergman rearrangement of sterically unencumbered acyclic 3-aza-3-ene-1,5-diynes
-
The factors that affect the kinetics of the aza-Bergman cyclization of aza-enediynes (C,N-dialkynyl imines) have not previously been elucidated. Here we report our kinetic studies of the aza-Bergman reactions of a series of 6-triisopropylsilyl and 6-unsub
- Feng, Liping,Kumar, Dalip,Kerwin, Sean M.
-
p. 2234 - 2242
(2007/10/03)
-