2117-11-5Relevant articles and documents
Formal metal-free γ-arylation of 1,3-dicarbonyl compounds: Via an isomerisation/1,4-addition/[3,3]-sigmatropic rearrangement sequence
Guan, Xi-Dong,Lu, Shi-Chao,Wen, Fu-Qiang
supporting information, p. 8964 - 8968 (2021/11/27)
A metal-free redox arylation of alkynes with sulfoxides has been developed to provide unconventional access to diverse γ-arylated 1,3-dicarbonyl compounds in an atom-economical manner. Mechanistic studies suggest that a conjugated allenone intermediate was generated in situ, which solves the problem of reactivity and regioselectivity of unsymmetrical dialkyl-substituted internal alkynes and enables the functionalisation of a broad range of substrates bearing electron-withdrawing functional groups. The resulting arylated 1,3-dicarbonyl compounds are versatile and useful building blocks for further functionalisation. This journal is
Regio-Divergent C—H Alkynylation with Janus Directing Strategy via Ir(III) Catalysis
Li, Xianwei,Liang, Guangxin,Shi, Zhang-Jie
supporting information, p. 929 - 934 (2020/06/02)
Directing strategy has been extensively exploited to maintain activity and selectivity for the rapid access to functionalized molecules and pharmaceutical targets. However, ‘one-to-one’ activation model was usually achieved through traditional directing strategy. Herein, we achieved ‘one-to-two’ activation model by slight modification of simple and practical ketoxime and amide functionality. With judicious choice of directing groups, Csp3—H and Csp2—H bond alkynylation reaction, and more significantly, dehydrogenative Csp3—H alkynylation, were realized, enabling the regio-divergent late-stage modifications of pharmaceuticals.
Alkyne derivative containing nitrogen-oxygen bond and preparation method and application thereof
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Paragraph 0134-0138, (2019/10/17)
The invention belongs to the technical field of organic synthesis, and in particular relates to an alkyne derivative containing a nitrogen-oxygen bond and a preparation method and application thereof.The provided alkyne derivative containing the nitrogen-oxygen bond has a structural formula as shown in a formula (I), wherein R1 and R2 are independently selected from hydrogen, a C1-C20 hydrocarbongroup, a C5-C30 aryl, a C5-C30 substituted aryl, or a C5-C30 aromatic heterocyclic group, and R3 is a substituted silicon group. The alkyne derivative containing the nitrogen-oxygen bond contains aneasily convertible nitrogen-oxygen bond, a primary amine and an alkynyl-containing polysubstituted alcohol compound with high added value can be obtained by reduction, and the derivative has a good application prospect in the field of organic synthesis. Moreover, the alkyne derivative containing the nitrogen-oxygen bond contains a silicon group which is directly linked to an alkyne and can be easily removed, and a terminal alkyne compound can be further obtained.
Synthesis of substituted α-methylene-γ-butyrolactones from chloroformates via palladium catalysed cyclisation-anion capture
Grigg,Savic
, p. 2381 - 2382 (2007/10/03)
Cyclisation of chloroformates onto proximate alkyne functionality in the presence of a Pd(0) catalyst followed by anion capture affords α-methylene-γ-butyrolactone derivatives in moderate to good yields.
A new, highly stereoselective approach to pyrrolidines via overall 5-endo-trig cyclisations of homoallylic tosylamides
Jones, Andrew D.,Knight, David W.
, p. 915 - 916 (2007/10/03)
Iodocyclisations of E-homoallylic tosylamides 7 lead to excellent yields of either 2,5-trans- or 2,5-cis-3-iodopyrrolidines (10 or 11), depending upon the reaction conditions.
Cumulated Ylides XX. Syntheses of (E)-α,β-Unsaturated Macrocyclic Lactones by Intramolecular Wittig-Olefination via Triphenylphosphoranylideneketene
Bestmann, Hans Juergen,Schobert, Rainer
, p. 419 - 423 (2007/10/02)
Two methods for closure of macrocyclic lactone rings by intramolecular Wittig reaction of (ω-oxoalkoxy)carbonylmethylenetriphenylphosphoranes are described.The latter are easily accessible by addition of the appropriate (free or protected) ω-hydroxyalkanals to the cumulated ylide triphenylphosphoranylideneketene.Examples are then given for the use of these methods in natural product synthesis.
NEW STRATEGY IN THE STEREOCONTROLLED SYNTHESIS OF THE SPIRO KETAL SUBUNIT OF MILBEMYCINS
Bac, Nguyen Van,Langlois, Yves
, p. 2819 - 2822 (2007/10/02)
A double Baeyer-Villiger oxidation of bicyclo heptane-2,5-dione and a stereocontrolled alkylation of the dianion derived from 4-pentyn-2-ol are the salient features of a new strategy in the stereocontrolled synthesis of the spiroketal moiety of milbemycins.
Vinyl Cations, 38. Synthesis and Solvolysis of 3-Substituted 1-Cyclobutenyl Nonaflates
Auchter, Gerhard,Hanack, Michael
, p. 3402 - 3413 (2007/10/02)
3-Methyl- (8a) and 3-cyclopropyl-1-cyclobutenyl nonaflate (8b) as well as 2-cyclopropyl-1-cyclobutenyl nonaflate (12) and the parent 1-cyclobutenyl nonaflate (3) were synthesized from the corresponding cyclobutanones and nonafluorobutanesulfonic anhydride (10).The solvolysis rates and the product compositions of the solvolyses in trifluoroethanol and trifluoroethanol/water mixtures were determined.All 1-cyclobutenyl nonaflates solvolyze via a SN1 mechanism involving the intermediate nonclassical 1-cyclobutenyl cation, which is additionally stabilized by the substituents in the 3-position.
