Prenyl acetate

Cyclohexane 3.2 OS-phosphate buffer pH 7.2 (1/1) Wheatgerm lipase Prenyl acetate hydrolysis — 0.68 7... 

One synthetic route to lavandulyl acetate starts with prenyl acetate, which dimerizes in the presence of a Friedel-Crafts catalyst, such as boron trifluoride-diacetic acid [74]. 

The palladium-catalyzed reaction of diboron with allyl acetates or chlorides is a convenient alternative to transmetallation method for the synthesis of functionalized boronates. The reaction of diboron 119 with allyl acetates309-312 smoothly occurred without the assistance of a base, whereas the presence of AcOK was critical for the coupling with allyl chlorides313 (Equation (57)). The boron atom coupled with the less-hindered terminal carbon giving the thermally stable (if)-allyl boronates. Thus, the (E)- and (Z)-cinnamyl acetate, chloride (entries 1-4), and their secondary derivatives (entries 7 and 8), all afforded an (if)-cinnamyl boronate. The borylation of prenyl acetate was slow (entry 6), but the corresponding chloride (entry 5) and tertiary derivative (entry 9) worked well for the same purpose (Equation (58)).309,310... 

Retinoids. A new procedure has been described for the synthesis of vitamin A [retinol (95)] and related compounds via ir-allyl Pd complexes. Thus prenyl acetate (96) with PdCl2 gave the complex (97), the structure of which was... 

SYNS 2-BUTEN-l-OL, 3-METHYL-, ACETATE DIMETHYL.M.LYL ACETATE 7,y-DIMETHYLALLYL ACETATE ISOPENT-2-ENYL ACETATE 3-METHYL-2-BUTENYL ACETATE PRENYL ACETATE... 

Photoinduced electron transfer from donors such as prenyl acetate, geranyl acetate, all-/ra/w-famesyl acetate, and all-/ra j-geranylgeranyl acetate to 1,4-dicyano-2,3,5,6-tetramethylbenzene, 1,4-dicyanonaphthalene, and 9,10-dicya-noanthracene in the presence of l,r-biphenyl as co-donor in acetonitrile produces the radical cation of biphenyl and the radical anion of the electron acceptors. Geranyl acetate is observed to photocyclise, and the mechanism of this process which involves reaction of its radical cation with water is discussed. Allyl glycosides (76) can be photodeprotected to give (77) via (78) by irradiating with di-t-butyl peroxide in the presence of bromotrichloro-methane. ... 

A similar cyclization reaction proceeded on treatment of 2-haloethanal allyl acetal and allyl 2-halophenyl ether with Grignard reagents in the presence of an Fe(II) salt catalyst [177]. Addition of phenylmagnesium bromide to a solution of 2-iodoethanal prenyl acetal 176a in the presence of a catalytic amount of Fe(ll)Cl2 gave the isopropenyl-substituted tetrahydrofuran derivative 177 in 52% yield with an isopropyl-substituted product 180 (13%) (Scheme 3.164). 

Isoprene epoxidized on the vinyl group (l,2-epoxy-3-methyl-3-butene, 14) would also be an attractive synthon for monoterpenoids if it were more readily accessible. Among the possible preparative methods (Scheme 2), acid-catalyzed isomerization of 2,3-epoxy-l-halo-3-methylbutanes (epoxidized prenyl halides) and dehydrohalogenation of the resulting isomers seemed the best route until chlorination of prenyl acetate (15, R = OAc) with hypochlorous acid was published. Dehydration of the mixture of products gave a maximum of the chloroacetate 16, which yielded the epoxide 14 with sodium hydroxide in methanol. ... 

A small number of hemiterpenes are used in perfumery, the most important of which are prenyl acetate and benzoate. Thioesters, such as those shown in Scheme 4.11, have extremely intense green odours reminiscent of galbanum, in which they occur naturally. The esters are usually prepared from prenyl chloride and the thioesters from the corresponding thiol and acid chloride. 

F.17) 2-Buten-l-ol, 3-methyl-, acetate, 3-methyl-2-butenyl acetate, isopentenyl acetate, prenyl acetate [1191-16-8]... 

Terpenoid Synthesis from Isoprene.—Some prenylation procedures have been reported earlier. An efficient conversion of prenyl chloride into prenyl acetate has been described and the synthon (31 X = OH) (Vol. 7, p. 10) has... 

The telomerization of a mixture of isoprene and prenyl acetate in ethyl acetate, catalysed by boron trifluoride, gives the usual complex mixture of acetates this includes geranyl and a-terpinyl acetates. Isoprene dimerizes in the presence of certain titanium or zirconium catalysts, e.g. ZrBusCl -f AlClEt2 + Ph3P, giving 70% of the hydrocarbon (8), 8% of (9), and 22% of trimers. Heggie and... 

Typical of the methods available for the preparation of 7t-allylpalladium complexes is the preparation of the crystalline compound 70 by heating prenyl acetate 71 in acetic acid with PdCl2 in the presence of copper(II) chloride, followed by chromatographic purification. Alkylation of 70 with the anion derived from the Ci5-sulphone 72 is then carried out in DMF in the presence of at least four equivalents of triphenylphosphine (two per Pd) and gives the crystalline C2o-sulphone 73 from which vitamin A may be obtained by ethoxide-catalysed elimination of phenylsulphinic acid [40] (Scheme 16). Despite the moderate yield (52%) in the alkylation step and the use of stoichiometric amounts of palladium, this synthesis of vitamin A (7) avoids the lengthy functionalization process that is often necessary with more conventional methods of carbon-carbon bond formation. 

A palladium complex 18 is obtained by reaction of an acetic acid/acetic anhydride solution of prenyl acetate with palladium (II) chloride in the presence of sodium chloride, sodium acetate and cupric chloride. This complex is employed in alkylation of the anion derived from the Ci5-sulphone 7 to give the precursor sulphone 12 (Scheme 5) [6]. Use of a large excess of PPhs (4 equiv. per Pd) in DMF as solvent is needed for smooth coupling and gives a 52% yield of (alI- )-y2. Exposure of 12 to NaOEt in boiling MeOH affords an 81% yield of vitamin A (17), which contains 67% of the (all-E)-isomer. 

Butenoic acid, polymer with ethenyl acetate. See VA/crotonates copolymer Vinyl acetate/crotonic acid copolymer 2-Butenoic acid, polymer with ethenyl acetate and ethenyl propanoate. See VA/crotonates/vinyl propionate copolymer 2-Butenoic acid propyl ester (E)-2-Butenoic acid propyl ester. See Propyl crotonate 2-Buten-1-ol, 2-ethyl-4-(2,2,3-trimethyl-3-cyclopenten-1-yl)-. See 2-Ethyl-4-(2,2,3-trimethyl-3-cyclopenten-1-yl)-2-buten-1-ol 2-Buten-1-ol, 3-methyl-, acetaU. See Prenyl acetate... 

Dimethylallyl acetate 3,3-Dimethylallyl acetate Y,Y-Dimethylallyl acetate. See Prenyl acetate Dimethylallyl alcohol. See3-Methyl-2-buten-1-ol 1,1-Dimethylallyl alcohol. See 2-Methyl-3-buten-2-ol... 

Isopentane thiol. See 3-Methyl-1-butanethiol Isopentanoic acid. See Isovaleric acid Isopentanoic acid, phenylmethyl ester. See Benzyl isovalerate Isopentanol. See Isoamyl alcohol lsopent-2-enyl acetate. See Prenyl acetate Isopentyl acetate. See Isoamyl acetate Isopentyl alcohol. See Isoamyl alcohol s-lsopentyl alcohol. See 3-Methyl-2-butanol Isopentyl alcohol acetate. See Isoamyl acetate Isopentyl alcohol, cinnamate. See Isoamyl cinnamate... 

Methyl-2-butenyl acetate. See Prenyl acetate 3-Methyl-2-butenyl benzoate. See Prenyl benzoate... 

Premium Gel. See Bentonite Premium Granular Gum Arabic] Premium Powdered Gum Arabic. See Acacia Premium Powdered Gum Karaya No. 1 Special] Premium Powdered Gum Karaya No. 7 Premium Powdered Gum Karaya No. 2 HV] Premium Powdered Gum Karaya No. 2 Premium Powdered Gum Karaya No. 3. See Karaya (Sterculia urens) gum Premium Spray Dried Gum Arabic. See, Acacia Prenol Prenol. See3-Methyl-2-buten-1-ol Prenyl acetate... 

Vertenol. See 3-Methyl-2-buten-1-ol Vertenol acetate. See Prenyl acetate Vertenol caproate. See Prenyl caproate Vertenol heptanoate. See Prenyl heptanoate Vertenol isobutyrate. See Prenyl isobutyrate Vertical Hydrated Lime MV-200. See Calcium hydroxide... 

Myrcenol Myrcenyl acetate Piperonyl acetone Prenyl benzoate fragrance, antiseptics Isobomyl acetate fragrance, aromatherapy Cedanwood oil fragrance, artificial jasmine Benzyl acetate fragrance, artificial lavandin Prenyl acetate fragrance, bath preps. 

Pinacol Pinane Pinanol Pinocarveol Pipeline d-Piperitone Piperonyl acetate Piperonyl acetone Prenyl acetate Prenyl benzoate Propenylguaethol Propionaldehyde p-Propyl anisole Propyl butyrate 3-Propylidenephthalide... 

Geranyl tiglate Linalyl formate Prenyl acetate fragrance, lavender detergents Dihydroterpinyl acetate fragrance, lemon y-Bisabolene fragrance, lilac scents Cinnamyl alcohol... 

Diisobutylaluminum hydride 214-730-4 Prenyl acetate 214-734-6 Ethyl linolenate 214-737-2... 

Many alcohols, aldehydes, and esters, with a 2-methylbutane skeleton, occur as minor components in essential oils. Not surprisingly, in view of the biosynthesis, the commonest oxidation pattern is that of prenol, that is, 3-methylbut-2-ene-l-ol. For example, the acetate of this alcohol occurs in ylang ylang and a number of other oils. Flowever, oxidation has been observed at all positions. Esters such as prenyl acetate give fruity top notes to oils containing them, and the corresponding thioesters contribute to the characteristic odor of galbanum. 

This essential oil, distilled from Chamaemelum nobile (L.) All., possesses a series of angelates in various concentrations. Bail (2009) published the following values for angelates and sped c esters isobutyl angelate 32.1%, 2-methylbutyl angelate 16.2%, isobutyl isobutyrate 5.3%, methyl 2-methylbutyrate 1.9%, prenyl acetate 1.4%, 2-methylbutyl 2-methylbutyrate 1.2%, and 2-methylbutyl acetate 1.2%. As most of these compounds are available as synthetic chemicals, adulteration can be done easily. Detection is done by the combination of GC-C-IRMS. 

In addition to l-chloro-2-methyl-4-acetoxybutene-2 (130), other C5 building blocks have also been tested with the C15 sulfone (13) to synthesize retinyl acetate (9). When this concept is realized industrially, cost-efficiency calculations may indicate that another C5 building block has to be used, so that the equation given may change slightly. It was also possible to alkylate the anion of the C 5 sulfone (13) with the dimeric allylpalladium tt complex (135) in the presence of a large excess of triphenylphosphine, the complex (135) being prepared from prenyl acetate and palladium(II) chloride (Manchand et al., 1978). 

A synthesis of 95% pure all-rran5 vitamin A has been achieved by the ir-allylpalladium complex coupling of appropriate Cs + Cis units in 41% yield. The reaction is accomplished when a stoicheiometric amount of the crystalline Pd chloride complex of prenyl acetate is coupled to the sulphinate of vinyl-/8-ionol. All five possible nor-analogues of all-rran5-geranylgeraniol have now been prepared by conventional procedures. The n.m.r. data are usefully... 

Hemiterpenoids are used mostly as intermediates in the synthesis of other terpenoids. The main exceptions are some esters of prenol that impart fruity top-notes in perfumery. Prenyl acetate (58), R = Me) and benzoate (58), R = Ph) are the two most important of these. 

Cascade Reactions. As the title compound is able to facilitate such a variety of synthetic steps, it is possible to envision a system where multiple steps are catalyzed in tandem in the same flask. The allylation-cyclization of phenols with prenyl acetate is an example of that type of reaction, involving the sequential activation of the ester and the alkene toward nucleophilic attack by two positions on the phenol (eq 38). ... 

Figure 24 Total ion chromatograms of washing powder. (A) SAFE versus (B) SDE. Key 1, Prenyl acetate 2, cw-3-Hexenyl acetate 3, 2-terL-Butylcyclohexyl acetate (cis-Agrumex) 4, 2-tert.-Butylcyclohexyl acetate (trans-Agnunex) 5, 1-Phenylethyl acetate 6, Geranyl acetate 7, Verdyl acetate.

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