A- allyl ethers

Tetrabromobisphenol A (TBBPA) is primarily used as a reactive flame retardant in epoxy resin circuit boards. Both hydroxyl groups on TBBPA can be reacted with epichlorohydrin under basic conditions to form the diglycidyl ether, which is widely used in epoxy resin formulations. TBBPA is also used in polycarbonate and ether polyester resins and is used as a chemical intermediate for the synthesis of tetrabromobisphenol A allyl ether, -bis(2-hydroxyethyl ether), -carbonate oligomer, and -diglycidyl ether. TBBA is also used as a flame retardant in plastics, paper, and textiles, and as a plasticizer in adhesives and coatings. 

Glycerol a-allyl ether. See Glyceryl-1 -allyl ether Glycerol epichlorhydrin. See Epichlorohydrin Glycerol esters of condensed castor oil fatty acids. See Polyglyceryl polyricinoleate... 

CAS 123-34-2 EINECS/ELINCS 204-620-4 Synonyms Allyl-(2,3-dihydroxypropane) ether a-Allyl glycerol ether Allyl glyceryl ether 1 -Allyloxy-2,3-propanedlol 3-Allyloxy-1,2-propanediol Ether, allyl glyceryl GAE Glycerln-1 -allyl ether Glycerol oc-allyl ether Glyceryl a-allyl ether 1,2-Propanedlol, 3-(2-propenyloxy)-Empirical CsH O,... 

Glyceryl a-allyl ether. See Glyceryl-1 -allyl ether Glyceryl caprate... 

Ether, allyl glyceryl GAE Glycerin-1-allyl ether Glycerol o-allyl ether Glyceryl a-allyl ether... 

Sol 4. (a) Allyl ether of 2-naphthol (I) on heating undergoes Claisen rearrangement to give l-aIlylnaphthalen-2-ol (II) and 3-allylnaphthalen-2-ol (HI). Reaction favors the formation of II as the aromaticity in the intermediate enone is lost only in one ring. However, in the formation of III aromaticity in the intermediate enone is lost in both the rings. 

Building on these results, Hanessian and co-workers devised an efficient protocol for the isomerisation of terminal olefins with minimal self-dimerisation or cross-metathesis by employing methanol to generate hydride complex 33 in situ from its parent 10. The procedure was successfully applied to a variety of allylic compounds, including O- and A-allyl ethers, and cleanly afforded the corresponding propenyl species as EjZ isomeric mixtures, without any further isomerisation or conjugation in the cases of ketones, esters and lactams. 

It could be assumed on the basis of the results of the DSC study on kinetics of the free-radical copolymerization of unsaturated polyesterimide resins that the reactivity of the tested monomers occurs in the sequence glycerol a-allyl ether > vinyltoluene > styrene > 2-hydroxyethyl methacrylate. On the other hand, the curing rate depends on the type of polyesterimide resin and varies for the products of one- and two-step synthesis. 

You have already seen that a carbon-heteroatom bond is easy to make, since we used such bonds as natural places for disconnections (frames 234 ft). It is good strategy therefore to make a carbon-heteroatom bond and then to transform it into a carbon-earbon bond. The Claisen rearrangement is one way to do this an ortho allyl phenol (B) made from an allyl ether (A) ... 

Allyllic ether 53 is oxidized regioselectively to the /3-alkoxy ketone 54, which is converted into the a,/i-unsaturated ketone 55 and used for annulation[99]. The ester of homoallylic alcohol 56 is oxidized mainlv to the 7-acetoxy ketone 57[99]. 

The 7, i5-unsaturated alcohol 99 is cyclized to 2-vinyl-5-phenyltetrahydro-furan (100) by exo cyclization in aqueous alcohol[124]. On the other hand, the dihydropyran 101 is formed by endo cyclization from a 7, (5-unsaturated alcohol substituted by two methyl groups at the i5-position. The direction of elimination of /3-hydrogen to give either enol ethers or allylic ethers can be controlled by using DMSO as a solvent and utilized in the synthesis of the tetronomycin precursor 102[125], The oxidation of the optically active 3-alkene-l,2-diol 103 affords the 2,5-dihydrofuran 104 in high ee. It should be noted that /3-OH is eliminated rather than /3-H at the end of the reac-tion[126]. 

The a-bromo-7-lactone 901 undergoes smooth coupling with the acetonyltin reagent 902 to afford the o-acetonyl-7-butyrolactone 903[763j. The o-chloro ether 904, which has no possibility of //-elimination after oxidative addition, reacts with vinylstannane to give the allyl ether 905, The o -bromo ether 906 is also used for the intramolecular alkyne insertion and transmetallation with allylstannane to give 907[764],... 

A method for protecting ketones and aldehydes is the formation of oximes, but sometimes further protection of the oximes is required. For this purpose, the oximes can be protected as allyl ethers. The oxime ethers ean be eleaved with triethylammonium formate in boiling dioxane[444]. The allyl ether of oximes is eleaved under mild conditions without attaeking the aeetal group in 677. 

The cyclohexadiene derivative 130 was obtained by the co-cyclization of DMAD with strained alkenes such as norbornene catalyzed by 75[63], However, the linear 2 1 adduct 131 of an alkene and DMAD was obtained selectively using bis(maleic anhydride)(norbornene)palladium (124)[64] as a cat-alyst[65], A similar reaction of allyl alcohol with DMAD is catalyzed by the catalyst 123 to give the linear adducts 132 and 133[66], Reaction of a vinyl ether with DMAD gives the cyclopentene derivatives 134 and 135 as 2 I adducts, and a cyclooctadiene derivative, although the selectivity is not high[67]. 

The mechanism of thermolysis and photolysis of ethers of 3-hydroxy-1,2-benzisoxazole has also been studied. Heating of the allyl ether (43) gave minor amounts of (44) and two benzoxazoles. Photolysis of (45) in methanol gave a benzisoxazole and an iminoester, via intermediate (46). Thermolysis at 600 °C gave a benzoxazole, a benzoxazolone and cyano-phenol (Scheme 16) (71DIS(D)4483). 

A slereoselectrve base catalyzed [2,3] sigmatropic rearrangement of allyl ethers to honwallylic alcohols (stereoselectrve)... 

NBS, CH3CN, H2O, 62-90% yield.The POM group has been selectively removed in the presence of an ethoxy ethyl ether, TBDMS ether, benzyl ether, p-methoxybenzyl ether, an acetate, and an allyl ether. Because the hydrolysis of a pentenyl 2-acetoxyglycoside was so much slower than a pentenyl 2-benzyloxyglycoside, the 2-benzyl derivative could be cleaved selectively in the presence of the 2-acetoxy derivative. The POM group is stable to 75% AcOH, but is cleaved by 5% HCl. 

Lithium diphenyphosphide (THF, 25°, 2 h HCl, H2O, 87% yield) selectively cleaves an aryl methyl ether in the presence of an ethyl ether.It also cleaves a phenyl benzyl ether and a phenyl allyl ether to phenol in 88% and 78% yield, respectively. ... 

Allyl ethers can be prepared by reaction of a phenol and the allyl bromide in the presence of base. Several reagents have been used to effect their cleavage ... 

NaAlH2(0CH2CH20CH3)2, PhCH3, reflux, 10 h, 62% yield/ An aryl allyl ether is selectively cleaved by this reagent (which also cleaves aryl benzyl ethers) in the presence of an A-allylamide. 

D. a-Allyl- -bromoelhyl ethyl ether. The same apparatus is used as in the preparation of allylmagnesium bromide. The flask is charged with an amount of the Grignard solution (part C) equivalent to 2.78 moles of allylmagnesium bromide (or chloride) and cooled in an ice bath. A solution of 580 g. (2.5 moles) of o , 3-dibromoethyl ethyl ether (part B) in an equal volume of anhydrous ether is added slowly with stirring over a period of 3-4 hours. The mixture is allowed to stand overnight and is then hydrolyzed with 75 ml. of 20% acetic acid followed by 500 ml. of water. The ether layer is separated, washed with four 100-ml. portions of 10% aqueous sodium bicarbonate solution followed by four 100-ml. portions of saturated aqueous sodium chloride solution, dried over 100 g. of anhydrous calcimn sulfate, and distilled under reduced pressure. The yield of colorless a-allyl-/3-bromoethyl ethyl ether is 370-396 g. (77-82% based on the a, 3-dibromoethyl ethyl ether), b.p. 72-75°/21 mm., 1.4600-1.4606. 

An interesting feature of the synthesis is the use of allyl as a two-carbon extension unit. This has been used in the stereospecific synthesis of dicyclohexano-18-crown-6 (see Eq. 3.13) and by Cram for formation of an aldehyde unit (see Eq. 3.55). In the present case, mannitol bis-acetonide was converted into its allyl ether which was ozonized (reductive workup) to afford the bis-ethyleneoxy derivative. The latter two groups were tosylated and the derivative was allowed to react with its precursor to afford the chiral crown. The entire process is shown below in Eq. (3.59). 

Perfluoroallyl fluorosulfate is prepared by the treatment oiperfluoropropene with sulfur tnoxide m the presence of boron catalysts [2, 3, 4, 5, 6, 7] (equation 2) Perfluoroisopropyl allyl ether reacts similarly to give 58% polyfluoroallyl fluorosulfate in a cis/trans ratio of 6 4 [S] Sultones are the exclusive products without catalyst. Polyfluoroolefins such as 2-hydropentafluoropropylene [9], (2,3-dichloropropyl)tri-fluoroethylene [70], perfluoropropene [2, i], perfluoroisopropyl alkenyl ethers [S], and acyclic polyfluoroallyl ethers [77] undergo sulfur trioxidation to regioselectively produce the corresponding P-sultones in high yield... 

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