Allylic phosphorates

Scheme 6.3 Some side chain reactions during polycondensation of allyl phosphoric dichlorides with aliphatic diols.

Acetic Anhydride Allyl Bromide Phosphoric Acid... 

One gram of 6,7-dihydro-5H-dibenz[c,e] azepine hydrochloride was dissolved in water, made alkaline with concentrated ammonia, and the resultant base extracted twice with benzene. The benzene layers were combined, dried with anhydrous potassium carbonate, and mixed with 0.261 g of allyl bromide at 25°-30°C. The reaction solution became turbid within a few minutes and showed a considerable crystalline deposit after standing 3 A days. The mixture was warmed VA hours on the steam bath in a loosely-stoppered flask, then cooled and filtered. The filtrate was washed twice with water and the benzene layer evaporated at diminished pressure. The liquid residue was dissolved in alcohol, shaken with charcoal and filtered. Addition to the filtrate of 0.3 gram of 85% phosphoric acid in alcohol gave a clear solution which, when seeded and rubbed, yielded 6-allyl-6,7-dihydro-5H-dlbenz[c,e] azepine phosphate, MP about 211°-215°C with decomposition. 

Pd-catalyzed nucleophilic allylic substitutions perform efficiently in an enan-tioselective way by using chiral phosphorous-containing ligands. Due to their high stability and convenient handling, M-containing ligands have recently... 

Analogously to the phosphorylation of alcohols with phosphoric azolides the phos-phinylation is carried out by means of phosphinic azolides (CH2CI2/C2H5OC2H5). In the following case a I2/C2H5OC2H5) protonated diphenylphosphinic imidazolide is used to give the allylic diphenylphosphinic esters in good yields ... 

In 1982, a new reaction was reported by Tamura and Ono namely, allylic nitro compounds undergo replacement of the nitro group by various nucleophiles in the presence of a palladium (0) catalyst.17a b 18a b The details of these reactions are discussed in Ref. 2b here, only some typical examples are presented. Carbon, sulfur, nitrogen, and phosphorous centered nucleophiles replace the nitro groups at the allylic positions. The reaction of allylic nitro compounds with triphenylphosphine is applied to the highly stereoselective olefination of aldehydes (Eqs. 7.15-7.18).19... 

Relatively few examples involving a phosphorous atom in the a-heteroatom-alkylcuprate have appeared [176]. Such cuprates have been treated with allylic and propargylic substrates, but have not been reported to undergo conjugate addition... 

Markovic and Hartwig isolated and characterized the first intermediate in iridium-catalyzed allylic substitution [100]. They isolated the metalacyclic iridium-phosphor-amidite fragment containing COD and the olefinic portion ofN- l -phenylallyl)aniline, the product of the allylic substitution reaction between cinnamyl carbonate and aniline (5 in Scheme 22). This complex containing the product of allylic substitution was first detected by NMR spectroscopy during catalytic reactions. It was then isolated, prepared independently, and shown to be chemically and kinetically competent to be an intermediate in allylic substitutions. 

Allylio monobromido can only bo obtained by the action of phosphorous tribromide on allylic alcohol —... 

AHC(18)337>. The 3-alkylbenzo[6 ]furans result from cyclodehydration of aryloxyacetones the most common dehydrating agents are sulfuric acid, phosphorus oxychloride and poly-phosphoric acid. The allyl ethers of phenols can be converted to 2-alkyl-2,3-dihydro-benzo[6]furan by heating with polyphosphoric acid, pyridine hydrochloride or magnesium chloride at 180 °C the intermediate o-allylphenol is not isolated. 

The addition of phosphites to allyl halides catalyzed by Pd° has been found to yield alkyl phosphorates (equation 65).215... 

It is possible to carry out an in situ Wittig reaction with a stabilized phosphorous ylide and an aldehyde obtained by a BaMnC>4 oxidation of a primary benzylic or allylic alcohol.77... 

An interesting route has been observed with dCMP (Schuchmann et al. 1983). The formation of the allylic radical upon elimination of phosphoric acid seems to be the driving force for reaction (281). Cyt is released in the subseqent reactions (282). The suggested mechanism has been supported by experiments in D20. 

Allyl bromide Hexamethyl phosphoric acid amide... 

Methoxy-4,5-azimidobenzoic acid l-Allyl-2-aminomethyl pyrrolidine Phosphoric anhydride... 

A mixture of phosphoric acid and trifluoroborane etherate was used by Hof mann-La Roche workers to prepare a rm-butyl ether and a rm-butyl ester in one pot from the homochiral p-hydroxy add 124.1 as shown in Scheme 4.124.225 The method can be applied to molecules containing an allylic triisopro pylsilyl ether [Scheme 4.125].143... 

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