Electrophilic intramolecular cyclization of functional derivatives of unsaturated compounds: IV. Cyclosulfenylation of 5-hexenoic acid amides and nucleophilic cleavage of reaction products
摘要:
Anilides of 5-hexenoic acid react with arylsulfenyl chlorides in nitromethane in the presence of lithium perchlorate affording products of electrophilic cyclization, N-{6-[(arylsulfanyl)methyl]tetrahydro-2H-pyran-2-ylidene}anilinium perchlorates. The treatment of the latter with sodium acetate or secondary cycloalkylamines in the presence of water results in the opening of the tetrahydropyran ring and provides anilides or cycloalkylamides of 6-arylsulfanyl-5-hydroxyhexanoic acid.
Effect of Substitution on the Intramolecular 1,3-Dipolar Cycloaddition of Alkene Tethered Münchnones
作者:Guillaume Bélanger、Myriam April、Étienne Dauphin、Stéphanie Roy
DOI:10.1021/jo061556t
日期:2007.2.1
dipolarophile and the münchnone on the intramolecularcycloaddition outcome was examined. It was found that either nonactivated or electron-poor alkenes can react with the münchnone if these alkenes are tethered at position 4 on the münchnone (2, R2 = alkene tether), whereas only an electron-poor alkene at position 2 (2, R3 = alkene tether) could undergo successful cycloaddition. Also, münchnones substituted
a C=C double bond is present in the molecule, an intramolecular cyclization process takes place in an exo mode with additional generation of a hydroxy group at the terminal position of the original olefin moiety to render a series of pyrrolidine and piperidine derivatives. In this paper, proofs are offered to conclude that, according to our assumption, an ionic mechanism rather than a radical one must
aided by native directing groups, using readily available pinacolborane (HBpin) and D2O as H– and D+ sources, respectively. Significantly, this tactic offers a complementary pattern to conventional hydrodeuteration methods that adduct H–D, or its surrogate, to unsaturated bonds. Both experimental data and density functional theory (DFT) studies demonstrated the critical role of the directing group in guiding
在远端 C(sp 3 )–H 键处安装氘原子是一项长期存在的合成挑战。通过链步策略和转移氢氘化的协同组合,我们在天然定向基团的帮助下,使用现成的频哪醇硼烷 (HBpin) 和 D 2 O ,展示了远端 C(sp 3 )–H 位点未活化烯烃的远程转移氢氘化作为 H –和 D +来源,分别。值得注意的是,这种策略为传统的加氢氘化方法提供了一种补充模式,该方法将 H-D 或其替代物加合物到不饱和键上。实验数据和密度泛函理论 (DFT) 研究都证明了引导基团在引导烯烃异构化过程中的关键作用。DFT 计算表明,在烯烃插入和异构化步骤中,是原位生成的 Ni(II)-氢化物而不是 Ni(I)-氢化物作为活性中间体发挥作用。
Synthesis of Substituted γ- and δ-Lactams via Pd-Catalyzed Alkene Carboamination Reactions
作者:Jordan R. Boothe、Yifan Shen、John P. Wolfe
DOI:10.1021/acs.joc.7b00041
日期:2017.3.3
substituted γ- and δ-lactams via palladium-catalyzedalkenecarboaminationreactions between aryl halides and alkenes bearing pendant amides is described. The substrates for these reactions are generated in 1–3 steps from commercially available materials, and products are obtained in good yield with up to >20:1 diastereoselectivity. The stereochemical outcome of the alkene addition is consistent with a
Electrophilic intramolecular cyclization of functional derivatives of unsaturated compounds: IV. Cyclosulfenylation of 5-hexenoic acid amides and nucleophilic cleavage of reaction products
作者:A. I. Vas’kevich、N. M. Tsizorik、V. I. Staninets、M. V. Vovk
DOI:10.1134/s1070428013080125
日期:2013.8
Anilides of 5-hexenoic acid react with arylsulfenyl chlorides in nitromethane in the presence of lithium perchlorate affording products of electrophilic cyclization, N-6-[(arylsulfanyl)methyl]tetrahydro-2H-pyran-2-ylidene}anilinium perchlorates. The treatment of the latter with sodium acetate or secondary cycloalkylamines in the presence of water results in the opening of the tetrahydropyran ring and provides anilides or cycloalkylamides of 6-arylsulfanyl-5-hydroxyhexanoic acid.