34317-22-1Relevant articles and documents
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).
Preparation of alkylated compounds using the trialkylphosphate
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Paragraph 0184-0185; 0211, (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
Graphene oxide: A convenient metal-free carbocatalyst for facilitating amidation of esters with amines
Patel, Khushbu P.,Gayakwad, Eknath M.,Shankarling, Ganapati S.
, p. 2661 - 2668 (2020/02/20)
Herein, we report a graphene oxide (GO) catalyzed condensation of non-activated esters and amines, that can enable diverse amides to be synthesized from abundant ethyl esters forming only volatile alcohol as a by-product. GO accelerates ester to amide conversion in the absence of any additives, unlike other catalysts. A wide range of ester and amine substrates are screened to yield the respective amides in good to excellent yields. The improved catalytic activity can be ascribed to the oxygenated functionalities present on the graphene oxide surface which forms H-bonding with the reactants accelerating the reaction. Improved yields and a wide range of functional group tolerance are some of the important features of the developed protocol.
