2035-85-0Relevant academic research and scientific papers
A Unified Catalytic Asymmetric (4+1) and (5+1) Annulation Strategy to Access Chiral Spirooxindole-Fused Oxacycles
Gao, Min,Gong, Xiangnan,Hu, Lin,Luo, Yanshu,Xia, Yuanzhi,Xu, Qianlan,Zhao, Yukun
supporting information, p. 19813 - 19820 (2021/08/03)
A unified catalytic asymmetric (N+1) (N=4, 5) annulation reaction of oxindoles with bifunctional peroxides has been achieved in the presence of a chiral phase-transfer catalyst (PTC). This general strategy utilizes peroxides as unique bielectrophilic four- or five-atom synthons to participate in the C?C and the subsequent umpolung C?O bond-forming reactions with one-carbon unit nucleophiles, thus providing a distinct method to access the valuable chiral spirooxindole-tetrahydrofurans and -tetrahydropyrans with good yields and high enantioselectivities under mild conditions. DFT calculations were performed to rationalize the origin of high enantioselectivity. The gram-scale syntheses and synthetic utility of the resultant products were also demonstrated.
A short biomimetic approach to the fully functionalized bicyclic framework of type A acylphloroglucinols
Couladouros, Elias A.,Dakanali, Marianna,Demadis, Konstantinos D.,Vidali, Veroniki P.
supporting information; experimental part, p. 4430 - 4433 (2009/12/24)
A biomimetic approach toward type A polyprenylated acylphlorogluclnols (PPAPs) Is described. The method Is based on a C-alkylation-cation cyclization reaction sequence, leading to a convenient buildup of molecular complexity, employing the simple and read
4-((PHENOXYALKYL)THIO)-PHENOXYACETIC ACIDS AND ANALOGS
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Page/Page column 68, (2008/06/13)
The invention features 4-((phenoxyalkyl)thio)-phenoxyacetic acids and analogs, compositions containing them, and methods of using them as PPAR delta modulators to treat or inhibit the progression of, for example, dyslipidemia.
Synthesis of [1.1.1]propellanes by bridging of bicyclo[1.1.0]butanes
Werner, Markus,Stephenson, David S.,Szeimies, Guenter
, p. 1705 - 1715 (2007/10/03)
Several [1.1.1]propellanes were synthesized by bridging the 1,3-positions of the corresponding bicyclo[1.1.0]butane. The synthesis of 1-bromo-3-(chloromethyl)bicyclobutanes and the bridging were carried out in a one-pot reaction by addition of 2.0 equiv. of MeLito 1,1-dibromo-2,2-bis(chlormethyl)-cyclopropanes 10. Three routes to 10 were investigated: Firstly, the Wittig reaction of 1,3-dichloroacetone leading to (chloromethyl)allyl chlorides 6 was, with the exception of 6m, successful only with Wittig reagents derived from primary alkyl halides. Secondly, reduction of diethyl alkylidenemalonates with LiAlH4 in benzene afforded carbinols 12 which were converted into 6 by reaction with N-chlorosuccinimide/ dimethyl sulfide. The cyclopropanation of 6 to 10 was achieved by reaction with bromoform/NaOH under phase-transfer catalysis conditions. Finally, starting from diethyl alkylidenemalonates, the sequence of reduction and cyclopropanation could be interchanged, according to the sequence 11 → 13 → 14 → 10. Propellanes 5b and 3 were reduced with LiAlH4 to bicyclo[1.1.1]pentanes 15b and e. 2-D INADEQUATE NMR spectra of 5d and 5p indicate that the coupling constants J(13C-13C) between the bridgehead positions are very small, i.e. 0.47 and 0.53 Hz, respectively. VCH Verlagsgesellschaft mbH, 1996.
Skipped cyclic ene- and dienediynes. 1. Synthesis, spectroscopic properties, and reactions of a new hydrocarbon ring family
Gleiter, Rolf,Merger, Roland,Nuber, Bernhard
, p. 8921 - 8927 (2007/10/02)
The three skipped cyclic C12H12 dienediynes, 4,9-dimethylene-1,6-cyclodecadiyne (1), (Z,Z)-4,10-cyclododecadiene-1,7-diyne (2), and 10-methylene-(Z)-4-cycloundecene-1,7-diyne (3), have been synthesized by cyclization of dilithium salts of diterminal enediynes with the corresponding dihalogenides. This simple approach only worked (with approx. 5% yield) when no CuCl catalyst was used. Besides 1-3, 4,9-diisopropylidene-1,6-cyclodecadiyne (30), the cyclic enediynes (Z)-4-cycloundecene-1,7-diyne (19) and (Z)-4-cyclododecene-1,7-diyne (20), as well as 4-methylene-1,6-cyclodecadiyne (22), 4-methylene-1,6-cycloundecadiyne (23), and their isopropylidene congeners 25 and 28 have been synthesized. Partial hydrogenation of 1-3 gives the corresponding homoconjugated tetraenes 37-39. The reaction of 30 with dicarbonyl(η5-cyclopentadienyl)cobalt yields a superphane of two cyclobutadiene units, stabilized by two CpCo moieties (47). The two cyclobutadiene rings are connected by four 2-isopropylidenepropano bridges. An X-ray investigation of the superphane shows that all four bridges adopt a pinwheel-like conformation.
