Ethyl senecioate

The addition of lithium alkoxydienolates to a,P-enones occurs exclusively in the l,4(a)-mode. For example, alkoxydienolate (202), obtained from ethyl senecioate, adds efficiently, in a tandem conjugate addition-allylation protocol, to cyclopentenone to afford the a,(3-functionalized cyclopentanone (203),153 In contrast, the lithium dienolate (204), from 5-methylbutenolide, affords exclusive y-alkylation,154 b while the analogous phthalide enolates (206) can be exploited to accomplish regiospecific polynuclear aromatic syntheses (Scheme 76).l54c ... [Pg.111]

F.45) 2-Butenoic acid, 3-methyl-, ethyl ester, ethyl 3-methylbut-2-enoate, ethyl 3-methylcrotonate, ethyl 3,3-dimethylacrylate, ethyl isobutenoate, ethyl senecioate [638-10-81... [Pg.179]

Butenoic acid, 3-methyl-, ethyl ester. See Ethyl senecioate... [Pg.588]

Ethyl isobutanoate. See Ethyl isobutyrate Ethyl isobutenoate. See Ethyl senecioate Ethylisobutylmethane. See Isoheptane Ethyl isobutyrate... [Pg.1753]

Ethyl methyl benzene. See Ethyl toluene N-Ethyl-p-methylbenzene sulfonamide. See Ethyl toluenesulfonamide Ethyl p-methylbenzenesulfonate. SeeEthyl-p-toluenesulfonate Ethyl 4-methyl benzoate Ethyl p-methylbenzoate. See Ethyl p-toluate Ethyl 2-methyl-2-butenate. See Ethyl tiglate Ethyl 3-methyl-2-butenoate. See Ethyl senecioate... [Pg.1760]

Ethyl 3-methylcrotonate. See Ethyl senecioate Ethyl a-methylcrotonate. See Ethyl tiglate Ethyl p-methylcrotonate. See Ethyl senecioate Ethyl (E)-2-methylcrotonate. See Ethyl tiglate... [Pg.1760]

S)-(-)-Citronellol L-Cystine 1,10-Decanediol Diethyl adipate Diethyl ketone Dihydroisojasmone Dodecene-1 Erucic acid 2-Ethyl-1-butanol Ethyl pivalate Ethyl senecioate D-Gluconic acid Heptanal diethyl acetal trans-3-Heptenyl acetate ... [Pg.5271]

Ethyl acetate Ethylacetoacetate Ethylene brassylate 2-Ethyl fenchol Ethyl 3-hexenoate 2-Ethylhexyl salicylate Ethyl 3-(methylthio) propionate Ethyl pelargonate Ethyl pivalate Ethyl senecioate... [Pg.5318]

Isopropyl propionate 211-319-1 Ethyl senecioate 211-320-7 Isopropyl butyrate 211-322-8... [Pg.6795]

Aldol condensation of the retro Cj5 aldehyde (284) with ethyl senecioate (285) in the presence of potassium amide gave 4,6-retroretinoic acid (286). This compound reacted with methyl iodide to give the methyl ester, which was reduced with lithium aluminum hydride to 4,6-retroretinol (287) ( a-vitamin A ). Treatment of (287) with triphenylphosphine hydrochloride gave the C20 phos-phonium salt (288), while oxidation of (287) with manganese(IV) oxide produced the aldehyde (282) (Isler, 1971). [Pg.69]

A number of converging syntheses of 3,4-didehydroretinoids employed the same strategies that have been successfully employed for the synthesis of the natural retinoids (1), (2), and (3). Alkali-catalyzed condensation of the dehydrogenated C 5 aldehyde (294) with ethyl senecioate (285) gave, after esterification, ether (295) or (296), which were converted to the alcohols (289) or (297), and to the aldehydes (290) or (298) (Schwieter et aL, 1962b). [Pg.70]

The Ci5 aldehyde (4) condensed with ethyl senecioate (285) in the presence of sodium amide or lithium amide to give (13Z)-retinoic acid (17), which was converted to the methyl ester and then reduced to give (13Z)-retinol (346). Oxidation of the latter gave (13Z)-retinaldehyde (41) (Matsui et aL, 1958). [Pg.77]

Condensation of the Cj5 aldehyde (347) with ethyl senecioate (285) in liquid ammonia or anhydrous ether in the presence of potassium amide gave (9Z)-retinoic acid (348), which was methylated in a conventional manner with diazomethane to give methyl (9Z)-retinoate (357). Reduction of (357) with lithium aluminum hydride gave (9Z)-retinol (132), which was oxidized with man-... [Pg.80]

A mixture of 12.7 g. frazis-dehydro-y -ionylideneacetaldehyde and 9.8 g. (1.3 moles) ethyl senecioate in abs. ether added dropwise to KNHg I NaNHa... [Pg.479]

Sand as diluent to prevent caking, 33,98 Saponification, of ethyl linoleate, 32, 78 of ethyl linolenate, 22, 84 of natural oils, 22, 75, 79, 82 Screen, protective, 22, 97 Seal, rubber tube, for stirrer shaft, 21,40 Senecioic acid, 23, 27 Separatory funnel, large, construction of, 23,10S... [Pg.61]

Thermolysis of the sulfone 58 gave 58% of a mixture of geraniol (25) and nerol (27) ethyl ethers. Starting from senecioic acid (59), Katzenellenbogen has continued studies of the addition of prenyl halides (15, R = halogen) to the dianion in presence of copper. Copper ion also influenced the addition of prenyl bromide (15, R = Br) to the anion of the V-methylamide of 59, its presence transforming a yield of 98% of the a-addition product to 83% of the y-product, geranic acid V-methylamide [as a mixture of (Z)- and ( )-isomers]. ... [Pg.288]

A general procedure has been published for the synthesis of retinoids, including vitamin A, by direct condensation of the side-chain, as ethyl 3,7-dimethylnona-2,4,6-trien-8-ynoate (80) to the appropriate cyclic ketone, e.g. 2,2,6-trimethyl-cyclohexanone (81). The acetylenic intermediate (82) is readily converted into vitamin A and derivatives. The side-chain reagent (80) is prepared in high yield by Emmons reaction between the acetylenic aldehyde (83) and the phospho-senecioate (84). In another synthesis of trans- tamm A, jS-ionylideneacetal-... [Pg.142]

Ethyl sorbate Ethyl undecanoate Ethyl vanillin Formic acid Furfuryl thioacetate Geranium maculatum oil a-D-Glucose pentaacetate Guaiol acetate Heptyl crotonate Heptyl isobutyrate Heptyl valerate Hexanal propylene glycol acetal cis-3-Hexenyl anthranilate cis-3-Hexenyl benzoate cis-3-Hexenyl crotonate cis-3-Hexenyl hexanoate 3-Hexenyl isovalerate cis-3-Hexenyl phenylacetate cis-3-Hexenyl senecioate Hexenyl-cis-3-valerate Hexyl alcohol Hexyl 2-furoate Hexyl lactate Hexyl nicotinate Hexyl phenylacetate Hexyl valerate Hydroxycitronellal residue Hydroxylamine sulfate 5-Hydroxy-4-octanone y-lonone... [Pg.5318]

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