Boord reaction

Olefin from the treatment of P-halo-alkoxide with zinc. Br R 

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The elimination of OR and halogen from P-halo ethers is called the Boord reaction. It can be carried out with zinc, magnesium, sodium, or certain other reagents.The... 

The process from the FMC company involves as the pivotal step an intramolecular stereoselective [2 + 1 [-cycloaddition. In a Prins reaction [94] of chloral and isobutene, followed by an isomerisation, a racemic, trichloromethyl-substituted aUyl alcohol is obtained. Reaction with the isocyanate from (R)-naphthylethyl-amine enables separation ofthe diastereomers by crystallisation. The carbamate is cleaved by trichlorosilane/triethylamine, thus permitting the recycling of the chiral auxiliary. The optically pure (R)-aUyl alcohol is reacted with diketene, to produce the / -keto-ester. After diazo transfer and basic cleavage, the diazoacetate is obtained catalysed by a copper salt, this is converted in a [2 + 1 ]-cyclo-addition into a bicyclic lactone. The Boord reaction (discovered by Cecil E. Boord in 1930) [95] finally gives (IR)-cis-permethric acid. [96]... 

Walsh proposed ease of reaction in the hydrogen abstraction step was in the order 3° 2° > 1° (229, 230). Boord has applied this idea (20, 21, 24, 25). If this order were to be accepted, it would have to be assumed that the rate of the hydrogen abstraction step is not controlling but something else, such as stability of peroxides (228) formed, determines knock. 

By analogy with the chlorination mechanism, in which we assume a chain reaction, Boord also suggests another chain mechanism with repeating links. He assumes that nitric acid undergoes decomposition at a high temperature to form nitric anhydride ... 

Boord and his co-workers (151) used this reaction as a proof of the identity of a reaction product believed to be vinylcyclopropane. The... 

Benzothiazoline-2-thiones (CI 11) and their derivatives can be prepared from o-amino thiophenols and carbon disulfide (method A) 166,221,282). On the industrial scale, these compounds, which are important vulcanization accelerators, are prepared from anilines, sulfur and carbon disulfide under pressure and at high temperature (200° C) (method B). In spite of many attempts, the mechanism of this reaction has not been established. Sebrell and Boord 211 mention the following plausible mechanisms ... 

Cyclic halo ethers also undergo reaction with Grignard reagents. 3-Chloro-tetrahydro-2-propylpyran is formed in 73% yield from 2,3-dichlorotetrahydro-pyran and propylmagnesium bromide.345 In a reaction analogous to the Boord synthesis, compounds of this structure are readily cleaved by sodium to the unsaturated alkanols 345,346... 

The 0X0 process, patented by Roelen in 1938, involved the addition of carbon monoxide and hydrogen to olefins using a cobalt catalyst at 150°C and 200 atmospheres. See BIOS 355, 7 for the Reppe-Ruhrchemie link. For the 0X0 process, see Milton Orchin, The 0X0 Reaction, in Benjamin T. Brooks, Cecil E. Boord, Stewart S. Kurtz, Jr., and Louis Schmerling, eds. The Chemistry of Petroleum Hydrocarbons, volume 3 (New York Reinhold, 1955), pp. 341-361 FIAT 1000 Klaus Weissermel and Hans-Jurgen Arpe, Industrielle organische chemie (Weinheim, 1976), translated by Alexander Mullen, Industrial Organic... 

Condensation reactions, such as the Boord synthesis, are good methods for converting aliphatic aldehydes [Eq. (3)] to substituted olefins via the preparation of dibromoethyl ethers, Grignard coupling, and elimination of bromoethoxy zinc. (See the referenced text for more detailed equations.)... 

Bechamp method, 129 Beckmann rearrangement, 94, 279 Benzilic acid rearrangement, 67-68 Benzoin condensation, 30 Bogoslovskii Reaction, 244 Boord synthesis, 17 Borsche synthesis, 244... 

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