Pseudocine substitution of 4-(mesyloxy)-2-cyclopentenones: an efficient route to 2,4-disubstituted 2-cyclopentenones
摘要:
Readily available mesylates 1a-d were found to undergo a novel substitution reaction. In the presence of a variety of nucleophiles, 1a-d underwent a net substitution in which the nucleophile was introduced vicinally (C-3) to the departing mesylate (C-4) and the double bond migrated to C-4/C-5. Lithium bromide, thiophenol, benzylamine, sodium azide, and the potassium salt of dimethyl malonate all led to substitution products in good yield. The reaction is thought to proceed by way of initial conjugate addition of the nucleophile, followed by enolate equilibration and beta-elimination of mesylate.
Silver catalyzed zinc Barbier reaction of benzylic halides in water
作者:Lothar W. Bieber、Elisabeth C. Storch、Ivani Malvestiti、Margarete F. da Silva
DOI:10.1016/s0040-4039(98)02199-6
日期:1998.12
Benzylic chlorides react in aqueous dibasic potassium phosphate under silver catalysis with aromatic aldehydes in the presence of zinc dust to give 1,2-diaryl alcohols in moderate to good yields. Dimerization to bibenzyls and reduction of the halide are important side reactions. A wide range of substituted aromatic and heteroaromatic aldehydes and of substituted benzylic chlorides can be used. Aliphatic
Cadmium-Mediated Carbonyl Benzylation in Tap Water
作者:Cunliu Zhou、Zhiyong Wang
DOI:10.1055/s-2005-865293
日期:——
Zn/CdCl 2 has been developed as a mediator in the benzylation of various aldehydes in tap water affording the corresponding alcohols in moderate to good yields. The addition of a catalytic amount of InCl 3 increases the yield of benzylation product significantly. It can selectively mediate the benzylation of aldehydes in the presence of ketones. A mechanism involving the formation of a cation it-complex
Chemoselective Benzylation of Aldehydes Using Lewis Base Activated Boronate Nucleophiles
作者:Michael R. Hollerbach、Timothy J. Barker
DOI:10.1021/acs.organomet.8b00085
日期:2018.5.14
A benzylation of aldehydes using primary and secondary benzylboronic acid pinacol esters is reported. Activation of the boronic ester with s-butyllithium rendered it nucleophilic toward aldehydes. The activatednucleophile chemoselectively transfers the benzyl group over the sec-butyl group, providing excellent yields of the benzylated products. 11B NMR experiments were performed to study the mechanism
据报道,使用伯和仲苄基硼酸频哪醇酯对醛进行苄基化。与硼酸酯的活化小号丁基锂渲染它亲核朝向醛。活化的亲核试剂化学选择性地将苄基转移到仲丁基上,从而提供了极佳的苄基化产物收率。进行11 B NMR实验以研究这种转化的机理。
[EN] SUMO INHIBITOR COMPOUNDS AND USES THEREOF<br/>[FR] COMPOSÉS INHIBITEURS DE SUMO ET UTILISATIONS ASSOCIÉES
申请人:HOPE CITY
公开号:WO2020028525A1
公开(公告)日:2020-02-06
There are disclosed, inter alia, methods of inhibiting an E1 enzyme, and compounds useful for inhibiting an E1 enzyme.
其中公开了抑制E1酶的方法,以及用于抑制E1酶的化合物。
Catalytic Asymmetric Synthesis of 8-Oxabicyclooctanes by Intermolecular [5+2] Pyrylium Cycloadditions
作者:Michael R. Witten、Eric N. Jacobsen
DOI:10.1002/anie.201402834
日期:2014.6.2
for this effect is analyzed using experimental and computational evidence. The resultant 8‐oxabicyclo[3.2.1]octane derivatives possess a scaffold common in naturalproducts and medicinally active compounds and are also versatile chiral buildingblocks for further manipulations. Several stereoselective complexity‐generating transformations of the 8‐oxabicyclooctane products are presented.