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Allyl acetone

Trans form) d2-Limonene (dipentene) Allocimene Trans isomer Allyl acetone Cis form... [Pg.254]

The perfume constituent 5-nonene-2-one (5) was obtained in 61 % yield via cross-metathesis of silylated allyl acetone with two equivalents of 4-octene (using Re207/Mo03/Al203/Me4Sn as catalyst) and elimination of the protecting group (Eq. 16) [40]. [Pg.571]

The perfume constituent non-5-ene-2-one is obtained in 61% yield via crossmetathesis of silylated allyl acetone with 2 equiv of oct-4-ene, reaction (18), using Re207/Mo03/Al203/Me4Sn as catalyst (Warwel 1989c). [Pg.187]

Benzylic halides resemble allylic halides m the readiness with which they form carbocations On comparing the rate of S l hydrolysis m aqueous acetone of the fol lowing two tertiary chlorides we find that the benzylic chloride reacts over 600 times faster than does tert butyl chloride... [Pg.445]

Only 2-alkylthiopyrimidines are made by the Principal Synthesis, using 5-alkylthiourea as one component. For example, ethoxymethylenemalononitrile (877) and 5-benzylthiourea in aqueous acetone at 20 °C give 4-amino-2-benzylthiopyrimidine-5-carbonitrile (878) (61JOC79) and ethyl 2-allyl-2-formylacetate and 5-methylthiourea in aqueous ethanolic alkali give 5-allyl-2-methylthiopyrimidin-4(3H)-one (6UOC4425). [Pg.136]

For most combinations of atoms, a number of molecular structures that differ fk m each other in the sequence of bonding of the atoms are possible. Each individual molecular assembly is called an isomer, and the constitution of a compound is the particular combination of bonds between atoms (molecular connectivity) which is characteristic of that structure. Propanal, allyl alcohol, acetone, 2-methyloxinine, and cyclopropanol each correspond to the molecular formula CjH O, but differ in constitution and are isomers of one another. [Pg.75]

When used at room temperature in the presence of an active platinum catalyst in an inert solvent, e.g., acetone or ethyl acetate, oxygen will oxidize nonhindered, saturated hydroxyl groups and exposed allylic alcohols. This reagent has found extensive use in sugar chemistry and is particularly suited for the selective oxidation of either 3a- or 3j -alcohols of steroids. Other hydroxyl groups on the steroid skeleton are much less sensitive to oxidation. As a result, this reaction has been used extensively in research on polyhydroxy cardiac-active principles, e.g., the cardenolides and bufadienolides, where the 3-hydroxyl group is easily oxidized without extensive oxidation or dehydration of other hydroxyl groups. The ordinarily difficult selective oxidation of the... [Pg.239]

Class 6 Poisons such as acetone cyanohydrin, acetonitrile, acrylonitrile, allyl alcohol, allyl chloride, airiline, epiclilorohydrin, lead alkyls, organophosphorus compounds. [Pg.187]

Differences in solubility of the reactants may for example be utilized as follows. Sodium iodide is much more soluble in acetone than are sodium chloride or sodium bromide. Upon treatment of an alkyl chloride or bromide with sodium iodide in acetone, the newly formed sodium chloride or bromide precipitates from the solution and is thus removed from equilibrium. Alkyl iodides can be conveniently prepared in good yields by this route. Alkyl bromides are more reactive as the corresponding chlorides. Of high reactivity are a-halogen ketones, a-halogen carboxylic acids and their derivatives, as well as allyl and benzyl halides. [Pg.113]

By boiling allyl bromide and pyrogallol dimethyl ether with acetone and potassium carbonate, he obtained a dimethoxyphenyl allyl ether, which was converted into dimethoxyallyl phenol by heating to 220°. On methylation this yields trimethoxyallyl benzene, identical with elemicin. [Pg.267]

A solution of 24.6 g of o-allyl-epoxypropoxybenzene dissolved in 250 ml of absolute ethanol saturated with ammonia was placed in an autoclave and heated on a steam-bath for 2 hours. The alcohol was then removed by distillation and the residue was redissolved in a mixture of methanol and ethylacetate. Hydrogen chloride gas was introduced into the solution. The hydrochloride salt was then precipitated by the addition of ether to yield 11.4 g of product. Five grams of the amine-hydrochloride thus formed were dissolved in 50 ml of methanol and 9 ml of acetone. The resulting solution was cooled to about 0°C. At this temperature 5 g of sodium borohydride were added over a period of 1 hour. Another 2.2 ml of acetone and O.B g of sodium borohydride were added and the solution was kept at room temperature for 1 hour, after which 150 ml of water were added to the solution. The solution was then extracted with three 100-ml portions of ether which were combined, dried over potassium carbonate, and evaporated. The free base was then recrystallized from petrol ether (boiling range 40°-60°C) to yield 2.7 g of material having a melting point of 57°C. [Pg.48]

B) Preparation of 7-A//y/oxy-4,8-Dimethylcoumarin 7-Hydroxy-4,8-dimethylcoumarin (191.3 g, 1.01 mols), anhydrous potassium carbonate (604 g, 4.37 mols), and allyl bromide (578 ml, 6.22 mols) were refluxed overnight in acetone (ca 3 liters) with mechanical stirring. The reaction mixture was concentrated nearly to dryness on a steam bath under re-... [Pg.1551]

Acetone can also he coproduced with allyl alcohol in the reaction of acrolein with isopropanol. The reaction is catalyzed with an MgO and ZnO catalyst comhination at approximately 400°C and one atmosphere. It appears that the hydrogen produced from the dehydrogenation of isopropanol and adsorbed on the catalyst surface selectively hydrogenates the carhonyl group of acrolein ... [Pg.230]

Resolution (enantiomers), 307-309 Resonance, 43-47 acetate ion and, 43 acetone anion and. 45 acyl cations and, 558 allylic carbocations and, 488-489 allylic radical and, 341 arylamines and, 924 benzene and, 44. 521 benzylic carbocation and, 377 benzylic radical and, 578 carbonate ion and. 47 carboxylate ions and, 756-757 enolate ions and, 850 naphthalene and, 532 pentadienyl radical and. 48 phenoxide ions and, 605-606 Resonance effect, 562 Resonance forms, 43... [Pg.1314]

The disclosure, in 1982, that cationic, enantiopure BINAP-Rh(i) complexes can induce highly enantioselective isomerizations of allylic amines in THF or acetone, at or below room temperature, to afford optically active enamines in >95 % yield and >95 % ee, thus constituted a major breakthrough.67-68 This important discovery emerged from an impressive collaborative effort between chemists representing Osaka University, the Takasago Corporation, the Institute for Molecular Science at Okazaki, Japan, and Nagoya University. BINAP, 2,2 -bis(diphenylphosphino)-l,l -binaphthyl (Scheme 7), is a fully arylated, chiral diphosphine which was introduced in... [Pg.349]

Bordwell and Cooper211 drew attention to the inertness of a-halosulfones and related compounds towards nucleophilic displacements of the halogen. Thus chloromethyl p-tolyl sulfone reacts with potassium iodide in acetone at less than one-fiftieth of the rate for n-butyl chloride. On the other hand, l-(p-toluenesulfonyl)-3-chloro-l-propene reacts about 14 times faster than allyl chloride. This contrast (and other comparisons) led the authors to attribute the inertness of a-halosulfones to steric hindrance, which was eliminated when the sulfonyl group was more remote from the reaction center. [Pg.529]

The rapid fabrication of covalently bonded ID functional molecular lines with predefined location, direction, and length provides a means to make a predesigned interconnection of molecular lines running along and across the dimer rows. Indeed, the perpendicularly connected allyl mercaptan and styrene lines or allyl mercaptan and acetone lines have been fabricated on the H-Si(l 00)-2 X 1 surface. °° 2 ... [Pg.171]

Both sides of acetone have been alkylated with different alkyl groups, in one operation, by treatment of the Al,lV-dimethylhydrazone of acetone with n-BuLi, followed by a primary alkyl, benzylic, or allylic bromide or iodide then another mole of n-BuLi, a second halide, and finally hydrolysis of the hydrazone. ... [Pg.555]


See other pages where Allyl acetone is mentioned: [Pg.94]    [Pg.1519]    [Pg.255]    [Pg.321]    [Pg.349]    [Pg.79]    [Pg.141]    [Pg.941]    [Pg.661]    [Pg.661]    [Pg.94]    [Pg.1519]    [Pg.255]    [Pg.321]    [Pg.349]    [Pg.79]    [Pg.141]    [Pg.941]    [Pg.661]    [Pg.661]    [Pg.179]    [Pg.29]    [Pg.85]    [Pg.63]    [Pg.301]    [Pg.401]    [Pg.229]    [Pg.241]    [Pg.297]    [Pg.113]    [Pg.98]    [Pg.309]    [Pg.329]    [Pg.737]    [Pg.105]    [Pg.346]    [Pg.22]    [Pg.548]    [Pg.1514]    [Pg.405]   
See also in sourсe #XX -- [ Pg.141 ]




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