The Williamson Ether Synthesis – Master Organic Chemistry
2014年10月24日 · The Williamson ether synthesis is a substitution reaction, where a bond is formed and broken on the same carbon atom. In this substitution reaction, a new C-O bond is formed, and a bond is broken between the carbon and the leaving group (LG) which is typically a halide or sulfonate.
What is the best reaction condition and preferred solvent for ...
NaH is insoluble in THF but you can use it. DMF is an alternative. Dry DMF at rt. to 60 degree and must be attention if bromide can make elimination in the presence of formed alkoxide first...
Alcohols and Ethers - Louisiana Tech University
A. Alcohols react with alkali metals, sodium hydride (NaH), or sodium amide (NaNH 2) to produce alkoxide ions. Phenols react with sodium hydroxide to give the phenoxide ion. Alkoxides and phenoxides are strong bases and are used as reagents.
Diazomethane is one of the most effective reagents for the preparation of methyl esters from carboxylic acids. The carboxylic acid protonates the diazomethane reagent to generate a diazonium-carboxylate ion pair, which collapses to form the methyl ester.
Direct insertion into the C–C bond of unactivated ketones with NaH ...
2023年9月14日 · Distinct from classical methods using strong bases (such as NaNH 2, RLi, and RMgX), at low temperature (<−60°C) in homogeneous solution, a NaH-mediated two-phase reaction in THF at 50°C enables the generation of the highly active aryne species in a controlled manner. The generated arynes can participate in an efficient C–C σ-bond ...
Reaction of metal alkoxides with alkyl halides or tosylates to give ethers. This is an S N2 reaction. Alkoxides are prepared by the reaction of an alcohol with a strong base such as sodium hydride, NaH H 3CCO CH 3 CH 3 H 3CI THF + H 3CCO CH 3 CH 3 CH 3 H 3CCOH C H 3 C H 3 H O C C + NaH THF Na+NaH - H2 + NaI Na SN2 Few restriction regarding the ...
An improved Williamson etherification of hindered alcohols …
1997年6月30日 · Typical procedure: A solution of 3 (6.58 mmol) in anhydrous THF (2 ml) was added to NaH (9.00 mmol) in THF (10 ml). 15-Crown-5 (1.52 ml, 7.5 mmol) was carefully added to the mixture. Diethyleneglycol ditosylate (2.96 mmol) in THF (5 ml) was added and the reaction was stirred at room temperature for a further 5 hours.
anionic cyclization reactions. • THF, –78 ºC 1. LDA CH3O • It was shown that a phthalide anion is a suitable reaction partner en route to 1-hydroxynaphthalenes: CH3 O CH3 CH3O OH 58% OH CH3 CH3O O OCH3 OCH3 O BF3•OEt2 O OCH3 CH2Cl2, 23 ºC 43% • Staunton-Weinreb Annulations CH3 OCH3 CH3O O O CH3O CH3O OH H O O TBSO CH3 O H O O TBSO ...
Synthetic Organic Reactions Mediated by Sodium Hydride
2019年11月1日 · In this work, we report that mixing NaH with NaI or LiI in tetrahydrofuran (THF) as a solvent provides a new inorganic composite, which consists of NaI interspersed with activated NaH, as...
Hydride Reduction by a Sodium Hydride–Iodide Composite
2016年2月16日 · This study presents a series of reduction reactions of nitriles, amides, and imines as enabled by NaH in the presence of LiI or NaI. This remarkably simple protocol endows NaH with unprecedented and unique hydride-donor chemical reactivity.