42238-15-3Relevant articles and documents
Preparation and reactions of 2'- and 3'-vinyl bromides of uracil-nucleosides: Versatile synthons for anti-HIV agents
Haraguchi,Itho,Tanaka,Miyasaka
, p. 3391 - 3394 (1991)
Bromination and successive oxidation of 1-[5-O-(t-butyldiphenyl-silyl)-3-deoxy-3-phenylseleno-β-D-xylofuranos yl]uracil yields the 2'- and 3'-vinyl bromides, which serve as synthons for 2'- or 3'-substituted 2',3'-didehydro-2',3'-dideoxyuridines via palla
Copper-Catalyzed Aerobic Oxidative Azo-Ene Cyclization
Kim, Junsu,Lee, Da Hye,Kim, Jinho
supporting information, p. 4728 - 4733 (2021/09/09)
A copper-catalyzed aerobic oxidative azo-ene cyclization has been developed. The developed CuI/DMAP/O2 system efficiently facilitates the aerobic oxidation of ene-containing hydrazides to azo compounds, which undergo azo-ene cyclizations for the synthesis of oxazolidinones. In addition, the present approach enables the synthesis of lactams, as well as a nitroso-ene cyclization. Preliminary mechanistic studies revealed that two carbonyl groups were essential for the successful azo-ene cyclization and that a concerted mechanism might be plausible for this azo-ene cyclization. (Figure presented.).
Multicatalytic approach to one-pot stereoselective synthesis of secondary benzylic alcohols
Casnati, Alessandra,Lichosyt, Dawid,Lainer, Bruno,Veth, Lukas,Dydio, Pawe?
supporting information, p. 3502 - 3506 (2021/05/10)
One-pot procedures bear the potential to rapidly build up molecular complexity without isolation and purification of consecutive intermediates. Here, we report multicatalytic protocols that convert alkenes, unsaturated aliphatic alcohols, and aryl boronic acids into secondary benzylic alcohols with high stereoselectivities (typically >95:5 er) under sequential catalysis that integrates alkene cross-metathesis, isomerization, and nucleophilic addition. Prochiral allylic alcohols can be converted to any stereoisomer of the product with high stereoselectivity (>98:2 er, >20:1 dr).
Iridium-Catalyzed Regioselective Hydroalkynylation of Internal Alkenes Directed by an Oxime
Gao, Peng-Chao,Li, Bi-Jie,Wang, Zi-Xuan
, p. 9500 - 9504 (2021/12/14)
We report here an iridium-catalyzed hydroalkynylation of allylic alcohols protected by an oxime group. Catalytic alkynylation occurs exclusively at the distal position of the alkene. This method generates γ-alkynyl alcohol oximes directly from internal alkenes and terminal alkynes. The oxime group can be readily removed to afford a free alcohol, thus providing an indirect route for the catalytic hydroalkynylation of allylic alcohols.
Synergistic Relay Reactions To Achieve Redox-Neutral α-Alkylations of Olefinic Alcohols with Ruthenium(II) Catalysis
Kan, Jian,Li, Chao-Jun,Li, Chen-Chen,Li, Jianbin,Lv, Leiyang,Qiu, Zihang
supporting information, p. 4544 - 4549 (2020/02/04)
Herein, we report a ruthenium-catalyzed redox-neutral α-alkylation of unsaturated alcohols based on a synergistic relay process involving olefin isomerization (chain walking) and umpolung hydrazone addition, which takes advantage of the interaction between the two rather inefficient individual reaction steps to enable an efficient overall process. This transformation shows the compatibility of hydrazone-type “carbanions” and active protons in a one-pot reaction, and at the same time achieves the first Grignard-type nucleophilic addition using olefinic alcohols as latent carbonyl groups, providing a higher yield of the corresponding secondary alcohol than the classical hydrazone addition to aldehydes does. A broad scope of unsaturated alcohols and hydrazones, including some complex structures, can be successfully employed in this reaction, which shows the versatility of this approach and its suitability as an alternative, efficient means for the generation of secondary and tertiary alcohols.
Transition-Metal-Free Allylic Borylation of 1,3-Dienes
Maza, Ricardo J.,Davenport, Elliot,Miralles, Núria,Carbó, Jorge J.,Fernández, Elena
supporting information, p. 2251 - 2255 (2019/04/10)
This work explains the reactivity of diboron reagents with 1,3-dienes in a transition-metal-free context. The sole addition of Na2CO3 (30 mol %) to bis(pinacolato)diboron in MeOH allows the 1,4-hydroboration of cyclic and noncyclic 1,3-dienes. The electronic influence on the substrate guarantees the conjugated 1,4-hydroboration versus 1,2-diboration. DFT calculations show that the distribution of charge in the allylic anion intermediate governs the selectivity toward 1,4-hydroboration, while the favored trans configuration in diene reagents determines the preference for the E allyl boronate products.
Copper-Catalyzed Perfluoroalkylation of Allyl Phosphates with Stable Perfluoroalkylzinc Reagents
Liu, Lihua,Bao, Xifei,Xiao, Hua,Li, Junlan,Ye, Feifan,Wang, Chaoqin,Cai, Qinhua,Fan, Shilu
, p. 423 - 434 (2019/01/08)
A general and practical method for copper-catalyzed cross-coupling of allyl phosphates with stable perfluoroalkylzinc reagents has been developed. The reaction proceeds under mild reaction conditions with high efficiency, good functional group tolerance, and high regio- A nd stereoselectivities and provides general, straightforward, and useful access to allyl-perfluoroalkyl compounds. Preliminary mechanistic studies reveal that the allyl copper intermediate may be involved in the catalytic cycle.
Formal Aza-Wacker Cyclization by Tandem Electrochemical Oxidation and Copper Catalysis
Yi, Xiangli,Hu, Xile
supporting information, p. 4700 - 4704 (2019/03/07)
In oxidative electrochemical organic synthesis, radical intermediates are often oxidized to cations on the way to final product formation. Herein, we describe an approach to transform electrochemically generated organic radical intermediates into neutral
Arene-ruthenium complexes with 2-(arylazo)phenol as ancillary ligand: Synthesis, characterization, and utilization in catalytic transfer-hydrogenation
Karmakar, Jit,Bhattacharya, Samaresh
, p. 39 - 44 (2019/03/08)
Reaction of 2-(arylazo)phenols (HL-R, where H represents the phenolic proton and, R = CH3, H and Cl) with [{Ru(p-cymene)Cl2}2] in the presence of triethylamine affords a group of three reddish-brown complexes of type [Ru(p-cymene)(L-R)Cl] in good yields. Structure of [Ru(p-cymene)(L-CH3)Cl] has been determined by X-ray crystallography. The 2-(arylazo)phenolate ligand (L-R) is coordinated to the metal center as a mono-anionic bidentate N,O-donor forming five-membered chelate ring. All the complexes are diamagnetic, and show characteristic 1H NMR signals. They also show intense absorptions in the visible and ultraviolet regions, which have been analyzed by TDDFT calculations. Cyclic voltammetry on the complexes shows two successive irreversible oxidations within 1.10–1.40 V versus SCE. The [Ru(p-cymene)(L-R)Cl] complexes are found to serve as efficient catalyst-precursor for the transfer-hydrogenation of aldehydes.
COMPOUNDS OF PHOSPHINANES AND AZAPHOSPHINANES, A PROCESS FOR THEIR PREPARATION AND PHARMACEUTICAL COMPOSITIONS CONTAINING THEM
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, (2018/02/27)
Compounds of formula (I) wherein: Ak1 represents an alkyl chain, X represents —(CH2)m—, —CH(R)—, —N(R)—, —CH2—N(R)—, —N(R)—CH2— or —CH2—N(R)—CH2—, m and R are as defined in the description, R1 and R2 each represent H when X represents —(CH2)m—, —CH(R)—, —N(R)—, —CH2—N(R)— or —N(R)—CH2—, or together form a bond when X represents —CH2—N(R)—CH2—, R3 represents NH2, Cy-NH2, Cy-Ak3-NH2 or piperidin-4-yl, Cy and Ak3 are as defined in the description, R4 and R5, which may be identical or different, each represent H or F, their optical isomers, and addition salts thereof with a pharmaceutically acceptable acid. Medicinal products containing the same which are useful in treating conditions requiring a TAFIa inhibitor.
