Réaction des amines aliphatiques sur les énolacétates et énoléthers des esters des acides α‐cétoniques

Abstract

C,H,,O, (184) Calculi: C 58,70 H 6,52"/, Trouvk C 58,67 H 6,73% Par les mhmes mkthodes que pour l'homologue inferieur ont &ti! obtenus: a-Ce'to-B-e'thyl-y-carbe'thoay-y-propyl-butyroZactone (IfZ b). Eb. 117-1 18O/0,1 Torr, Cl,H,,O, (242) Calculi. C 59,50 H 7,44q.b TrouvA C 59,25 H 7,51y0 Enolacdtate I Vb. Eb. 133--134O/0,1 Torr, di0 = 1,116, ng = 1,4635. or-Cdto-B-$thyl-y-~ro~yZ-y-Zactone ( Bb). Eb. 93-94O/0,05 Torr, di0 = 1,071, n : = C9H1403 (170) Calculi: C 63,53 H 8,2476 Trouvi: C 62,98 H 8,41% Enolace'tate Vlb. Eb. 109-110°/0,05 Torr, di0 = 1,080, n$' = 1,4667. Cl,H,,O, (212) Calculi: C 62,26 H 7,55"/0 Trouvi: C 62J3 H 7,52y0 B. Enolhthers et amines (ammoniac). a-Ethozy-acrylate d'e'thylel,). La mBthode deStevens & Sherr'j) fut appliquke avec les modifications suivantes: 70 g d'anhydride phosphorique et 50 g de di6thylacetal du pyruvate di:thyle sont verses dans un ballon Claisen de 500 ml muni d'une petite colonne de 5 B 8 cm, puis chauffks. AprAs une min env. la ri:act,ion s'amorce. On verse alors lentement un melange de 130 g de di6thylaci:tal et 80 g de pyridine en maintenant un chauffage tel qu'il y rtit un 1i:ger reflux sans distillation. dy = 1,117, n s = 1,4762.C,,H,,O, (284) Calculk C 59,l.i H 7,04% Trouvk C 59,OO H 6.98% 1,4848.15) Par titrage au NaOH 0,2-n. 16) Abandon& B la temperature ambiante, I'a-Qthoxy-acrylate d'ethyle commence k se polymkriser aprks 8 B 10 semaines. Le dkrivi: cc-acktoxyli: se polymerise dija a p r h 1 B 2 semaines. Ces esters restent intacts pendant plusieurs mois si on les conserve a 00 en presence d'hydroquinone.

A Probable Flavoring Principle in Vegetable‐Protein Hydrolysates

“…3, step d) ; this fact, together with the'evidence that it exists predominantly in its enolic form, identifies it as a-hyclroxy-P-methyl-A"8B-y-hexenolactone (IIb) . The same compound has previously been described by Monnin ( 1957)) who prepared it by reaction of methyl a-ketobutyrate with secondary aliphatic amines, but made no reference to its flavoring characteristics ; Monnin's synthesis has been repeated in this laboratory, and the product obtained was identical with that now described. The formation of a highly flavored lactone by decarboxylation of an essentially flavorless carboxylactone finds an interesting parallel in the behavior of the a-carboxy-y (or-a) -1actones of Cs to C&, which are latent flavoring compounds in synthetic butter flavor (St011 et al, 1964).…”

“…The Cg homologue, a-keto-y-valerolactone (III) has been described by Rossi et al (1948)) but the authors did not mention its flavoring characteristics ; however, an unstable compound, isomeric with (III) but of unknown structure, was isolated as a flavor carrier from soy sauce (Yokotsuka,195s). CH2CH3 CH3 CH2CH2CH3 (Ill) (IV) The Cs homologue, a-keto-&ethyl-y-enantholactone (IV), has been synthesized in this laboratory by the method of Monnin (1957), and it had a flavor much weaker than, and different in character from, that of the C, compound. Although the literature on other a-keto-r-lactones--carrying alkyl groups in the & or y-positions-is quite extensive (Schinz et al, 1947 ;Schinz et al, 1948 ;Monnin, 1957)) no reports on their flavor have been made.…”

“…CH2CH3 CH3 CH2CH2CH3 (Ill) (IV) The Cs homologue, a-keto-&ethyl-y-enantholactone (IV), has been synthesized in this laboratory by the method of Monnin (1957), and it had a flavor much weaker than, and different in character from, that of the C, compound. Although the literature on other a-keto-r-lactones--carrying alkyl groups in the & or y-positions-is quite extensive (Schinz et al, 1947 ;Schinz et al, 1948 ;Monnin, 1957)) no reports on their flavor have been made. The correlation between structure and organoleptic quality of compounds within this group should constitute a fruitful area for further study.…”

Neighboring Group and Substituent Effects in Organosulfur Compounds

“…Indeed, even the usual addition reactions onto C=C double bonds, such as those of amines [114], either fail to occur here or proceed different [112,114,117] from those of the u-alkylthioacrylic acid derivatives. This also supports the conclusion that the special reactivity of the a-alkylthioacrylic acid derivatives is caused by the ability of the thioether group to act both as electron donor and electron acceptor.…”

Darstellung und sensorische Eigenschaften von alkylsubstituierten 2‐Hydroxy‐buten(2)‐oliden(1,4) und strukturverwandten Verbindungen

“…ihren Estern erfolgen [I,5 ,61. Ein Nachteil dieses Verfahrens ist, da13 der 4-Substituent zwangslaufig I C-Atom mehr aufweist als der 3-Substituent.…”