Search results
Results from the WOW.Com Content Network
The Williamson ether synthesis is an organic reaction, forming an ether from an organohalide and a deprotonated alcohol . This reaction was developed by Alexander Williamson in 1850. [ 2 ] Typically it involves the reaction of an alkoxide ion with a primary alkyl halide via an S N 2 reaction .
Sodium phenoxide reacts with alkylating agents to afford alkyl phenyl ethers: [2] NaOC 6 H 5 + RBr → ROC 6 H 5 + NaBr. The conversion is an extension of the Williamson ether synthesis. With acylating agents, one obtains phenyl esters: [citation needed] NaOC 6 H 5 + RC(O)Cl → RCO 2 C 6 H 5 + NaCl
For example, from a solution of tetrachloroauric acid, the oxonium ion [H 7 O 3] + has been isolated as the salt [(H 7 O 3)(15-crown-5) 2][AuCl 4]. Neutron diffraction studies revealed a sandwich structure, which shows a chain of water with remarkably long O-H bond (1.12 Å) in the acidic proton, but with a very short OH•••O distance (1. ...
Alexander Williamson. Williamson is credited for his research on the formation of unsymmetrical ethers by the interaction of an alkoxide with a haloalkane, known as the Williamson ether synthesis. He regarded ethers and alcohols as substances analogous to and built up on the same type as water, and he further introduced the water-type as a ...
Williamson ether synthesis; R−Br + OR' − → R−OR' + Br − (S N 2) The Wenker synthesis, a ring-closing reaction of aminoalcohols. The Finkelstein reaction, a halide exchange reaction. Phosphorus nucleophiles appear in the Perkow reaction and the Michaelis–Arbuzov reaction. The Kolbe nitrile synthesis, the reaction of alkyl halides ...
For example, the synthesis of macrocidin A, a fungal metabolite, involves an intramolecular ring closing step via an S N 2 reaction with a phenoxide group as the nucleophile and a halide as the leaving group, forming an ether. [2] Reactions such as this, with an alkoxide as the nucleophile, are known as the Williamson ether synthesis.
In solution, the alkali metal derivatives exhibit strong ion-pairing, as expected for the alkali metal derivative of a strongly basic anion. Structure of the Li 4 (OBu-t) 4 (thf) 3 cluster, highlighting the tendency of alkoxides to aggregate and bind ether ligands.
An early example is the dialkylation of a nickel dithiolate: [2] The corresponding alkylation in the absence of a metal ion would yield polymers. Crown ethers arise from dialkylations that are templated by alkali metals. [3] Other template reactions include the Mannich and Schiff base condensations. [4]