for the synthesis of a valuable class of α‐aminomethylacrylates via the Baylis–Hillman reaction of different aldehydes with methyl acrylate followed by acetylation of the resulting allylic alcohols and SN2′‐type amination of the allylic acetates. Asymmetric hydrogenation of these diverse olefinic precursors using rhodium(Et‐Duphos) catalysts provided the corresponding β2‐amino acid derivatives with excellent
通过一种新的策略,通过不同醛类的Baylis-Hillman反应与丙烯酸甲酯的合成,然后合成的烯丙醇的乙酰化和乙酸烯丙酯的S N 2'型胺化反应,合成了有价值的α-氨基甲基丙烯酸酯类。使用铑这些不同的烯属前体的不对称氢化(ET-DUPHOS)催化剂提供了相应的β 2个具有优异的对映选择性的α-氨基酸衍生物和非常高的反应性(高达> 99.5%ee值和S / C = 10,000)。的(第一加氢Ž) -构型底物,研究了β的合成2氨基酸衍生物。对于该反应,还公开了底物几何形状和位阻对反应性和对映选择性的高影响。这个协议提供了用于光学纯β制备高度实用的,容易的和可扩展的方法2 -氨基酸和它们的衍生物在温和的反应条件下进行。
Efficient Transformation of Alkyl 3-nitro-5-(aryl/alkyl)isoxazole-4-carboxylates into 3-amino- and 3-hydrazinyl-5-aryl/alkyl-isoxazole-4-carboxylates in Aqueous Solution
作者:Sushobhan Mukhopadhyay、Dinesh S. Barak、Ilesha Avasthi、Sanjay Batra
DOI:10.1002/adsc.201700881
日期:2017.11.23
An efficient protocol for transforming alkyl 3‐nitro‐5‐(aryl/alkyl)isoxazole‐4‐carboxylates into 3‐amino‐ and 3‐hydrazinyl‐5‐aryl/alkyl‐isoxazole‐4‐carboxylates is described. The reaction that is carried out in aqueous acetonitrile solution generally afford the products without any chromatographic purification. Investigations with the substrate scope reveal that this protocol is compatible only when
[EN] NOVEL COMPOUNDS USEFUL AS POTENTIAL INSECT ANTIFEEDANT AND A PROCESS FOR THE PREPARATION THEREOF<br/>[FR] NOUVEAUX COMPOSÉS UTILES COMME ANOREXIGÈNE POTENTIEL POUR INSECTES ET PROCÉDÉ DE PRÉPARATION ASSOCIÉ
申请人:COUNCIL SCIENT IND RES
公开号:WO2017109795A1
公开(公告)日:2017-06-29
The present invention relates to novel compounds of general formula A: Particularly, the present invention relates to compounds which are useful as antifeedant against the major agricultural pest Spodoptera litura and thus useful as potential insect antifeedants. Further, the present invention relates to a process for the preparation of novel compounds of general formula A having insect antifeedant activity.
The preparation of N-containing α,β-unsaturated carboxylate derivatives from α-silylamine and Baylis-Hillmanadducts under visible light irradiation was reported. The formation of α-aminoalkyl radical is regioselective compared with the previous reports. The reaction was successfully performed without additional additives under mild conditions.
Synthesis of 3,4,5-Trisubstituted Isoxazoles from Morita-Baylis-Hillman Acetates by an NaNO<sub>2</sub>/I<sub>2</sub>-Mediated Domino Reaction
作者:Shashikant U. Dighe、Sushobhan Mukhopadhyay、Shivalinga Kolle、Sanjeev Kanojiya、Sanjay Batra
DOI:10.1002/anie.201504529
日期:2015.9.7
3‐nitro‐5‐(aryl/alkyl)isoxazole‐4‐carboxylates is described. In a cascade event, initial Michael addition of NaNO2 to the MBH acetate furnishes the allylnitro intermediate which undergoes I2‐catalyzed oxidative α‐CH nitration of the nitromethyl subunit followed by [3+2] cycloaddition to afford the title compounds. Structural elaborations of these highly substituted isoxazoles by SNAr reactions and
本文描述了一种有效的NaNO 2 / I 2介导的Morita-Baylis-Hillman(MBH)乙酸盐单酯转化为3-硝基--5-(芳基/烷基)异恶唑-4-羧酸烷基酯的方法。在一个级联事件,初始迈克尔加成纳米2到MBH醋酸配料其经历我的allylnitro中间2催化的氧化α-C 的硝基甲基亚基h的硝化,接着[3 + 2]环加成,得到标题化合物。这些高度取代的异恶唑通过S N Ar反应和氢解进行结构精制可以得到有用的产品。