Methallyl alcohol

When allylic alcohols are used as an alkene component in the reaction with aryl halides, elimination of /3-hydrogen takes place from the oxygen-bearing carbon, and aldehydes or ketones are obtained, rather than y-arylated allylic alcohoIs[87,88]. The reaction of allyl alcohol with bromobenzene affords dihydrocinnamaldehyde. The reaction of methallyl alcohol (96) with aryl halides is a good synthetic method for dihydro-2-methylcinnamaldehyde (97). 

This method of preparation is suitable for producing primary alkyl lactates but is unsatisfactory for /3-methallyl lactate because the strong mineral acid catalyzes the rearrangement of methallyl alcohol to isobutyraldehyde. Methyl lactate can be made conveniently (80-85% yield) by heating 1 mole of lactic acid condensation polymer with 2.5-5 moles of methanol and a small quantity of sulfuric acid at 100 for 1-4 hours in a heavy-walled bottle, such as is used for catalytic hydrogenation with a platinum catalyst. 

Although the introduction of a substituent at both C-a and C-P may be expected to destabilize the transoid state of rearrangement due to additional 1,2-allylic interactions, the tendency to form an -double bond exclusively is retained in the synthesis of trisubstituted olefins as well. The first such report, shortly following the initial Evans report , was made by Grieco who achieved a completely stereospecific general synthesis of ( )-y-substituted methallyl alcohols, including the synthesis of racemic ( )-nuciferol (45, equation 24) . Subsequently, other examples of nearly or completely stereospecific syntheses of ( )-) , y-substituted allylic alcohols have also been pub-lished - " . On the other hand, in the synthesis of y,y-disubstituted allylic alcohols a diminished stereoselectivity has been observed. In this case, the /Z ratio depends on the... 

Polyoxyalkylene ethers of allyl alcohol or methallyl alcohol... 

The copolymers may be mixed with other demulsifiers, in particular with alkoxylated novolaks and copolymers that are obtainable by copolymerization of one or more polyoxyalkylene ethers of allyl or methallyl alcohol with vinyl esters of alkyl monocarboxylic acids. 

J. Fock, E. Esselbom, and W. Hoehner. Use of copolymers of polyoxy-alkylene ethers of allyl or methallyl alcohols and acrylic or methacrylic esters as emulsion breakers for crude oil containing water (Verwendung von Copolymerisaten von Polyoxyalkylenethem des Allyl- und/oder Methallylalkohols und Acryl- oder Methacrylestem als Dismulgatoren fur Wasser enthaltendes Erdol). Patent DE 3513550,1986. 

Free-radical multicomponent copolymerization of dialkylstannyl maleates or dialkylstannyl dimethacrylates with methallyl alcohol (or (J-hydroxyalkyl acrylates) and vinyl monomers (sryrene, methacrylic acid or methacrylamide) yields polymeric powders. Due to their storage and thermal stability and impact strength they are used as protective coatings 79). 

Metanilic acid, all6 Methacholine chloride, a49 Methacrolein, m27 Methacrolein diacetate, m32 Methallyl alcohol, m400 Methallyl chloride, cl82... 

A variety of rhodium complexes also catalyze the isomerization of allylic alcohols to saturated carbonyl compounds. RhH(CO)(PPh3)3 quantitatively isomerized methallyl alcohol to isobutylaldehyde at 70°C in trifluoroethanol (Equation (11 )).42... 

CHLOROCYCLOBUTANE, 51, 106 Mesitylene, cyanation, 50, 54 METHALATION OF 2-METHYLPYRIDINE DERIVATIVES ETHYL 6-METHYL-PYRIDINE-2-ACETATE, 52, 75 Metalation, directed, 53, 59 Methallyl alcohol, with phenyl-mercuric acetate to yield 2-methyl-3-phenylpropional-dehyde, 51, 17 METHALLYLBENZENE, 52, 115 7r-Methallylnickel bromide, 52, 115... 

Phenylmercuric acetate, with methallyl alcohol to yield 2-methyl-3-phenylpropion-aldehyde, 51, 17 1-PHENYL-1,3-PENTADIYNE, 50,... 

Phenyl isocyanate, with ethyl hydrazine-carboxylate to give 4-phenyl-l-car-bethoxysemicarbazide,51,122 Phenylmercuric acetate, with methallyl alcohol to yield 2-methyl-3-phenyl-propionaldehyde, 51, 17 1-PHENYL-1,3-PENTADIYNE, 50, 97 1-PHENYL-1,4-PENTADIYNE. 50, 97 a-Phenylpentanal, from 2-benzyl-4,4,6-trimethyl-5,6-dihydro-l,3(4H)-... 

Methallyl alcohol was obtained from Eastman Organic Chemicals. 

The reagent is prepared in three steps from methallyl alcohol (38% yield). 

The elimination of the hydridopalladium group to the allylic position causes the formation of 3-substituted carbonyl compounds when allylic alcohols are reacted with organic halides (39). For example, when iodobenzene is reacted with methallyl alcohol, 2-methyl-3-phenylpropanal was formed in 91% yield along with 4% of 2-methyl-2-phenylpropanal ... 

The prototype for this structural class is 2-methyl-2-propen-l-ol (methallyl alcohol), from which asymmetric epoxidation generates optically active 2-methyloxiranemethanol. Like gly-cidol, 2-methyloxiranemethanol has been difficult to obtain by stoichiometric asymmetric epoxidation, but with the use of the catalytic version, reasonable quantities, are now produced [4] and the compound has become commercially available. In situ derivatization also can be used to recover this epoxy alcohol from the epoxidation reaction. Progress in the isolation of 2-methyloxiranemethanol is reflected in entries 1-3 of Table 6A.3, and the results of in situ derivatization are revealed by entries 4-6. The enantiomeric purity of 2-methyloxiranemethanol produced in this way is very good (92-95% ee), and improvement to 98% ee is observed after recrystallization of the 4-nitrobenzoate derivative. 

Mesyl chloride, m32 Metanilic acid, all9 Methacholine chloride, a49 Methacrolein, m24 Methallyl alcohol, m3 85 Methallyl chloride, cl64... 

Mercury(II) pivalate, 319 Mercury(II) trifluoroacetate, 320 Mesembranol, 169 a-Methallyl alcohol, 258 Methanesulfinyl chloride, 248 Methanesulfonic acid, 321 Methanesulfonyl chloride, 322 Methanol-sodium tetraborate, 322 Methoxyamine, 322-323 et Methoxy-a-arylacctic acid esters, 411 p-Methoxybenzyl ethers, 166, 167 Mcthoxycarbonylketene, 340, 341 4(R)-Methoxycarbonyl-l,3-thiazolidine-2-thione, 323-324... 

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