758-96-3Relevant articles and documents
Preparation of alkylated compounds using the trialkylphosphate
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Paragraph 0217; 0229, (2021/11/02)
[Problem] trialkylphosphate strong base used reaction agent, a carboxylic acid, a ketone, an aldehyde, amine, amide, thiol, ester or Grignard reagent to a variety of substrates, and/or high efficiency to generate a highly stereoselective alkylation reaction, the alkylated compounds capable of producing new means. [Solution] was used as the alkylating agent in the alkylation of compound trialkylphosphate, strongly basic reaction production use. [Drawing] no
Amide bond formation in aqueous solution: Direct coupling of metal carboxylate salts with ammonium salts at room temperature
Nielsen, John,Tung, Truong Thanh
supporting information, p. 10073 - 10080 (2021/12/10)
Herein, we report a green, expeditious, and practically simple protocol for direct coupling of carboxylate salts and ammonium salts under ACN/H2O conditions at room temperature without the addition of tertiary amine bases. The water-soluble coupling reagent EDC·HCl is a key component in the reaction. The reaction runs smoothly with unsubstituted/substituted ammonium salts and provides a clean product without column chromatography. Our reaction tolerates both carboxylate (which are unstable in other forms) and amine salts (which are unstable/volatile when present in free form). We believe that the reported method could be used as an alternative and suitable method at the laboratory and industrial scales. This journal is
Regio- And Stereoselective (S N2) N -, O -, C - And S -Alkylation Using Trialkyl Phosphates
Banerjee, Amit,Hattori, Tomohiro,Yamamoto, Hisashi
, (2021/06/16)
Bimolecular nucleophilic substitution (S N 2) is one of the most well-known fundamental reactions in organic chemistry to generate new molecules from two molecules. In principle, a nucleophile attacks from the back side of an alkylating agent having a suitable leaving group, most commonly a halide. However, alkyl halides are expensive, very harmful, toxic and not so stable, which makes them problematic for laboratory use. In contrast, trialkyl phosphates are inexpensive, readily accessible and stable at room temperature, under air, and are easy to handle, but rarely used as alkylating agents in organic synthesis. Here, we describe a mild, straightforward and powerful method for nucleophilic alkylation of various N -, O -, C - and S -nucleophiles using readily available trialkyl phosphates. The reaction proceeds smoothly in excellent yield, and quantitative yield in many cases, and covers a wide range of substrates. Further, the rare stereoselective transfer of secondary alkyl groups has been achieved with inversion of configuration of chiral centers (up to 98% ee).
Direct amidation of acid fluorides using germanium amides
Hayatifar, Ardalan,Elifritz, Emily A.,Bloom, Molly B.,Pixley, Kaitlyn M.,Fennell, Christopher J.,Weinert, Charles S.
supporting information, p. 4490 - 4493 (2021/04/12)
Amide functional groups are an essential linkage that are found in peptides, proteins, and pharmaceuticals and new methods are constantly being sought for their formation. Here, a new method for their preparation is presented where germanium amides Ph3GeNR2convert acid fluorides directly to amides. These germanium amides serve to abstract the fluorine atom of the acid fluoride and transfer their amide group -NR2to the carbonyl carbon, and so function as amidation reagents.
Catalytic Enantioselective α-Fluorination of 2-Acyl Imidazoles via Iridium Complexes
Xu, Guo-Qiang,Liang, Hui,Fang, Jie,Jia, Zhi-Long,Chen, Jian-Qiang,Xu, Peng-Fei
supporting information, p. 3355 - 3358 (2016/12/09)
The first highly enantioselective α-fluorination of 2-acyl imidazoles utilizing iridium catalysis has been accomplished. This transformation features mild conditions and a remarkably broad substrate scope, providing an efficient and highly enantioselective approach to obtain a wide range of fluorine-containing 2-acyl imidazoles which are found in a variety of bioactive compounds and prodrugs. A large scale synthesis has also been tested to demonstrate the potential utility of this fluorination method.
Ru-catalyzed direct amidation of carboxylic acids with N-substituted formamides
Bi, Xiaojing,Li, Junchen,Shi, Enxue,Wang, Hongmei,Gao, Runli,Xiao, Junhua
, p. 8210 - 8214 (2016/11/23)
The direct amidation of carboxylic acids with N-substituted formamides has been accomplished via ruthenium catalysis. In the presence of ruthenium catalyst, a versatile range of carboxylic acids and N-substituted formamides undergoes amidation reaction to produce synthetically useful amides in good yields. C[dbnd]O in amide product came from benzoic acid but not N-substituted formamides, and which was confirmed by Isotope experiment.
Transfer Hydrogenation of Nitriles, Olefins, and N-Heterocycles Catalyzed by an N-Heterocyclic Carbene-Supported Half-Sandwich Complex of Ruthenium
Mai, Van Hung,Nikonov, Georgii I.
, p. 943 - 949 (2016/05/09)
In the presence of KOBut, N-heterocyclic carbene-supported half-sandwich complex [Cp(IPr)Ru(pyr)2][PF6] (3) (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) catalyzes transfer hydrogenation (TH) of nitriles, activated N-heterocycles, olefins, and conjugated olefins in isopropanol at the catalyst loading of 0.5%. The TH of nitriles leads to imines, produced as a result of coupling of the initially formed amines with acetone (produced from isopropanol), and showed good chemoselectivity. Reduction of N-heterocycles occurs for activated polycyclic substrates (e.g., quinoline) and takes place exclusively in the heterocycle. The TH also works well for linear and cyclic olefins but fails for trisubstituted substrates. However, the C = C bond of α,β-unsaturated esters, amides, and acids is easily reduced even for trisubstituted species, such as isovaleriates. Mechanistic studies suggest that the active species in these catalytic reactions is the trihydride Cp(IPr)RuH3 (5), which can catalyze these reactions in the absence of any base. Kinetic studies are consistent with a classical inner sphere hydride-based mechanism of TH.
Oxidative coupling of alcohols and amines over bimetallic unsupported nanoporous gold: Tailored activity through mechanistic predictability
Wichmann, Andre,B?umer, Marcus,Wittstock, Arne
, p. 70 - 74 (2015/01/30)
An unsupported nanoporous gold catalyst is employed for the direct coupling of primary alcohols and amines to the corresponding amides in the liquid phase. Among others, the reaction of methanol and dimethylamine to the industrially relevant dimethylformamide proceeds smoothly at 40°C (turnover frequency≈40 h-1). The activation of molecular oxygen is identified as a key parameter. Doping of the unsupported catalyst by an admetal (Ru, Ag) is used to increase the activity of the catalyst considerably for this reaction (turnover frequency ≈ 100 h-1).
Iron-catalysed, general and operationally simple formal hydrogenation using Fe(OTf)3 and NaBH4
MacNair, Alistair J.,Tran, Ming-Ming,Nelson, Jennifer E.,Sloan, G. Usherwood,Ironmonger, Alan,Thomas, Stephen P.
supporting information, p. 5082 - 5088 (2014/07/08)
An operationally simple and environmentally benign formal hydrogenation protocol has been developed using highly abundant iron(iii) salts and an inexpensive, bench stable, stoichiometric reductant, NaBH4, in ethanol, under ambient conditions. This reaction has been applied to the reduction of terminal alkenes (22 examples, up to 95% yield) and nitro-groups (26 examples, up to 95% yield). Deuterium labelling studies indicate that this reaction proceeds via an ionic rather than radical mechanism.
Bromination of enamines from tertiary amides using the petasis reagent: A convenient one-pot regioselective route to bromomethyl ketones
Kobeissi, Marwan,Cherry, Khalil,Jomaa, Wissam
supporting information, p. 2955 - 2965 (2013/09/02)
An original one-pot synthesis of bromomethyl ketones is achived using the Petasis reagent (dimethyltitanocene) as a key for enamine generation. Several amides were used to test the limits of the procedure by changing either the alkyl chain R or the amino portion of the starting materials. The enamines generated in situ were allowed to react with bromine at low temperature followed by hydrolysis to yield bromomethyl ketones in excellent yields (85 to 95%). Mechanistic details and optimum conditions for the reaction are briefly discussed. The present approach offers several advantages such as regioselectivity in enamine formation, good yields, mild reaction conditions, and ease of experimentation.
