Reaction of certain geometrically defined 1,1-dioxy-4-alkyl- and -4,4-dialkyl-substituted buta-1,3-dienes with halogenated quinones does not involve Diels-Alder or Michael addition chemistry. Instead, rapid competitive oxidation of the dienes to give 2,4-dienoate esters was observed. This new reaction involves strong spatial association between diene and quinone, hydrogen being transferred specifically from the (4E)-alkyl group. Its scope is compared with addition of the same terminally substituted dienes towards the reactive non-quinonoid dienophile tetracyanoethylene.
硼酸化共轭多烯被广泛用作合成结构单元,用于制备许多生物活性分子。然而,对这些构建块的访问受到限制。在这项研究中,硼酸化共轭三烯是通过 Ru 催化的交叉二聚反应合成的,用于交叉偶联反应。[Ru(萘)(1,5-cod)] (10 mol %) 在室温下催化二苯乙炔与 ( E )-丁二烯-1-基硼酸频哪醇酯的反应,在苯中生成 (1 E ,3 E , 5 Z )-5,6-二苯基六-1,3,5-三烯-1-基硼酸频哪醇酯在10分钟内以93%的产率生成。使用戊-1-yn-1-基硼酸二异丙酯与 ( E )-戊二烯酸甲酯进行类似处理,得到 (2E ,4 E ,6 E )-7-(二异丙氧基硼烷基)-6-丙基六-2,4,6-三烯酸酯,产率为89%。通过交叉二聚化合成了一系列单和二硼化共轭三烯,并评估了它们在交叉偶联反应中的潜在用途。使用该协议,海蛞蝓信息素 navenone B 的全合成仅通过三个步骤实现,总产率为
Selective Alkenylation and Hydroalkenylation of Enol Phosphates through Direct CH Functionalization
作者:Xu‐Hong Hu、Xiao‐Fei Yang、Teck‐Peng Loh
DOI:10.1002/anie.201506437
日期:2015.12.14
Rh‐catalyzed direct CH functionalization reaction of enol phosphates was developed. The method is applicable to a variety of coupling partners, including activatedalkenes, alkynes, and allenes, and leads to the formation of various valuable alkenylated and hydroalkenylated enol phosphates through the action of the phosphate directing group. The versatility and utility of the coupling products were demonstrated
Rhodium-Catalyzed Intermolecular Chelation Controlled Alkene and Alkyne Hydroacylation: Synthetic Scope of β-<i>S</i>-Substituted Aldehyde Substrates
作者:Michael C. Willis、Helen E. Randell-Sly、Robert L. Woodward、Steven J. McNally、Gordon S. Currie
DOI:10.1021/jo060582o
日期:2006.7.1
The use of β-S-substituted aldehydes in rhodium-catalyzed intermolecularhydroacylation reactions is reported. Aldehydes substituted with either sulfide or thioacetal groups undergo efficient hydroacylation with a variety of electron-poor alkenes, such as enoates, in Stetter-like processes and with both electron-poor and neutral alkynes. In general, the reactions with electron-poor alkenes demonstrate
<scp>Pd‐Catalyzed</scp>
Asymmetric Synthesis of 3,
<scp>4‐Dihydroisoquinolinones</scp>
From
<scp>
<i>N</i>
‐Ts‐Benzamides
</scp>
and 1,
<scp>3‐Dienes</scp>
作者:Tae Kyun Kim、So Won Youn
DOI:10.1002/bkcs.12227
日期:2021.3
A Pd(II)‐catalyzed asymmetric oxidative annulation of N‐Ts‐benzamides with 1,3‐dienes using a chiral pyridine‐oxazoline‐type ligand for the regio‐ and stereoselective synthesis of chiral 3,4‐dihydroisoquinolinones has been developed.
C-3 ALKYL AND ALKENYL MODIFIED BETULINIC ACID DERIVATIVES
申请人:BRISTOL-MYERS SQUIBB COMPANY
公开号:US20140243298A1
公开(公告)日:2014-08-28
Compounds having drug and bio-affecting properties, their pharmaceutical compositions and methods of use are set forth. In particular, alkyl and alkenyl C-3 modified betulinic acid derivatives that possess unique antiviral activity are provided as HIV maturation inhibitors, as represented by compounds of Formulas I, II, III and IV:
a compound of Formula I
a compound of Formula II
a compound of Formula III
and a compound of Formula IV
These compounds are useful for the treatment of HIV and AIDS.
Solid-phase synthesis of heterocycles via palladium-catalyzed annulation
作者:Yao Wang、Tai-Nang Huang
DOI:10.1016/s0040-4039(98)02337-5
日期:1998.12
Solid-phase linked o-iodoanilines (4) and o-iodophenol (9) reacted with 1,3- and 1,4-dienes in the presence of palladium acetate to generate highly substituted indolines, tetrahydroquinolines, hydrobenzofurans and hydrobenzopyrans, which provided an efficient way for making heterocyclic molecule libraries.