Schmid, H.'s team published research in Helvetica Chimica Acta in 36

Schmid, H. published the artcileThe constitution of fulvoplumierin. II, Computed Properties of 3115-28-4, the publication is Helvetica Chimica Acta (1953), 1468-89, database is CAplus.

cf. C.A. 48, 1365a. Fulvoplumierin (I), hydrogenated in AcOEt over 5% Pd-CaCO₃ poisoned with Pb, absorbed 2.0 mol H to form 46% tetrahydrofulvoplumierin (II), C₁₄H₁₆O₄, yellow needles (from EtOH), m. 75-6° (reduces Tollens reagent, and gives a yellow color with EtONa in Me₂CO), and a little hexahydrofulvoplumierin (III). II in AcOEt was hydrogenated over Pd-CaCO₃ to 64% III. Ozonization of II in CHCl₃ gave BuCO₂H (p-toluidide, m. 69-71°, mixed m.p. 70-2°), also obtained by oxidation of II with KMnO₄. I, hydrogenated in AcOEt over Pd-CaCO₃, absorbed 2.9 mol H to give a mixture, separated by distillation and chromatog. into 1.5% II; 36% III, C₁₄H₁₈O₄, colorless needles (from MeOH-H₂O), m. 43.0-3.2°, b_0.02 120-30°, has 1 MeO group, no active H, slowly reduces Tollens reagent; 3.5% isohexahydrofulvoplumierin (IV), C₁₄H₁₈O₄, m. 74-4.5° (from MeOH-H₂O) (m.p. depressed by II), b_0.02 120°, has 1 MeO group, slowly reduces Tollens reagents; 8% octahydrofulvoplumierin (V), C₁₄H₂₀O₄, b_0.01 at 130°; and an oil, which was saponified to a monocarboxylic acid (VI), C₁₃H₁₈O₄, m. 91-2.5° (from C₆H₆-petr. ether), equivalent weight 246, λ_maximum 243 mμ (log ε 3.88) (in EtOH). III in AcOH, hydrogenated over PtO₂, absorbed 2.8 mol H and gave 15% decahydrofulvoplumierin (VII), C₁₄H₂₂O₄, m. 41.5-3.0°, and 68% of an acid (VIII), C₁₄H₂₄O₄. III did not react with MeNH₂.HCl in EtOH, or with Ac₂O, AcOH, and AcONH₄, or with CH₂N₂ in Et₂O. III, treated 20 h. with N NaOH at 125°, consumed 3 equivalents NaOH; acidification gave HCO₂H, identified as HCONHPh (m. and mixed m.p. 45.5-6.5°), and 88% of a dibasic acid (IX), C₁₂H₁₈O₄, m. 159-60° (from Et₂O or Me₂CO-H₂O), equivalent weight 115, pK₁ 4.25, pK₂ 7.00, having 1 C-Me (Kuhn-Roth oxidation), no MeO. Ozonolysis of III in EtCl at -14° gave HCO₂H (identified as HCONHPh), (CO₂H)₂, and 2-butylglutaric acid (X), C₉H₁₆O₄, m. 89-40.5°, mixed m.p. 39.5-41°, equivalent weight 99, pK₁ 4.16, pK₂ 5.24. X, m. 40-1° (from Et₂O-C₅H₁₂), was prepared in good yield by acid hydrolysis of BuC(CO₂Et)₂CHCH₂CO₂Et, b_0.23 128°, obtained in 72% yield by condensation of BuCH(CO₂Et)₂ and BrCH₂CH₂CO₂Et with Na in EtOH. IX was unaffected when heated 1 h. with 5% HCl at 180°. IX, hydrogenated over PtO₂ in AcOH, absorbed 1.0 mol H and gave an oily dibasic acid (XI), C₁₂H₂₀O₄, b_0.01 150°, equivalent weight 119, pK₁ 4.56, pK₂ 5.90. IX, heated 30 min. with Ac₂O at 155-60°, yielded a colorless add anhydride (XII), C₁₄H₁₈O₄, m. 70.5-1°, pK 2.52, equivalent weight 255, giving an intensive violet color with FeCl₃ and a pos. CHI₃ test, and forming stable salts which give back XII on acidification. Ozonolysis of IX in AcOEt at -14° gave 1.83 mol CO₂ and AcCH₂CH₂CHBuCO₂H (XIII), C₁₀H₁₈O₂, equivalent weight 195, having 2 C-Me group, and giving a pos. CHI₃ test; Clemmensen reduction of XIII gave Bu₂CHCO₂H (XIV), b₁₃, 150-70°, 2,4,6-tribromoanilide, m. and mixed m.p. 203.5-4.5° β-naphthylamide, m. and mixed m. 136-7.5°. For comparison with XIV, BuCHEt(CH₂)₂CO₂H (piperazine salt, m. 110°); [2,4,6-tribromoanilide, m. 96.5-7.0° (from EtOH)], was prepared by reduction of BuCHEtCO₂H with LiAlH₄ to BuCHEtCH₂OH, b₁₂ 79°, conversion to the bromide, condensation to BuCHEtCH₂CH(CO₂H)₂, m. 99.0-9.5°, and decarboxylation. The UV spectrum of IX showed it to be an α,β-unsaturated acid, and the formation of XII, X, and XIII established IX as being 3-butyl-2-carboxy-1-cyclopentene-1-acetic acid. 2-carboxy-1-cyclopentene-1-acetic acid (XV), C₈H₁₀O₄, m. 187°, equivalent weight 86, pK₁ 4.19, pK₂ 6.60, has an UV spectrum similar to that of IX, and was converted by boiling Ac₂O to an acid anhydride similar to XII, 3-hydroxy-4-acetyl-6,7-dihydrocyclopenta[c]pyran-1(5H)-one (XVI), C₁₀H₁₀H₄, m. 170-1°, colorless needles (from Me₂CO-H₂O), equivalent weight 203, pK 2.30, giving an intense violet color with FeCl₃. XII and XVI also have similar UV spectra in acids and in bases and show similar titration curves with NaOH, as do IX and XV. XII is therefore 3-hydroxy-4-acetyl-7-butyl-6,7-dihydrocyclopenta[c]pyran-1-(5H)-one, III is Me 7-butyl-6,7-dihydrocyclopenta[c]pyran-1(5H)-one-4-carboxylate, and XI is 3-butyl-2-carboxycyclopentane-1-acetic acid. IV, hydrogenated over PtO₂ in AcOH, absorbed 2.5 mol H and gave a mixture of VII and VIII. Ozonolysis of IV in CHCl₃ at -20° gave BuCO(CH₂)₂CO₂H (XVII), identified as its p-nitrophenylhydrazone, m. and mixed m. 149-50° (from EtOH-H₂O). XVII, m. 52-3° (from Et₂O-C₅H₁₂ or EtOH-H₂O), was prepared by saponification of its Et ester, b₁₃ 114°, obtained in 55% yield from EtO₂CCH₂CH₂COCl and Bu₂Cd in C₆H₆. From its UV spectrum (λ_maximum 285 mμ), IV has both double bonds conjugated with the carboxy group, and is therefore Me 7-butyl-5,6-dihydrocyclopenta[c]pyran-1(3H)-one-4-carboxylate. V, hydrogenated in AcOH over PtO₂, absorbed 1.0 mol H, and gave VII. Saponification of V yielded a small amount of a hydroxy dicarboxylic acid (XVIII), C₁₃H₂₀O₅, m. 132.5-3.0° (from Et₂O-petr. ether or Me₂CO-H₂O), equivalent weight 133, pK₁, 5.30, pK₂ 6.52, λ_maximum 232 mμ (log ε 4.02) (in EtOH), which does not lactonize easily. XVIII is probably 2-(2-carboxy-3-butyl-2cyclopenten-1-yl)-3-hydroxypropionic acid, and V is either Me 7-butyl-3,4,6,7-tetrahydrocyclopenta[c]pyran-1(5H)-one-4-carboxylate or Me 7 -butyl-4,4a,5,6-tetrahydrocyclopenta[c]pyran-1(3H)-one-4-carboxylate or a mixture of both forms. By analogy, and from its UV spectrum, VI is 7-butyl-3,4,6,7-tetrahydrocyclopenta[c] pyran-1(5H)-one-4-carboxylic acid or 7-butyl-5,6,7,7a-tetrahydrocyclopenta[c]pyran-1(3H)-one-4-carboxylic acid. I, hydrogenated completely in AcOH over PtO₂, gave VII and a mixture of other products which was saponified and then oxidized; KMnO₄ gave (CO₂H)₂, XVII, and a lactonic acid (XIX), C₁₃H₂₀O₄, m. 87.5-8.5°, equivalent weight 247; H₂CrO₄ gave BuCO₂H, PrCO₂H, and (CH₂CO₂H)₂. VII is Me 7-butylhexahydrocyclopenta[c]pyran-1(3H)-one-4-carboxylate, XIX is the corresponding free acid, and VIII is 2-(2-carboxy-3-butylcyclopentyl)propionic acid. The UV spectrum of II shows a double bond, conjugated with those in the pyrone ring, which must be in the cyclopentane ring, since oxidation of II gave BuCO₂H; II is probably Me 7-butylcyclopenta[c]pyran-1(5H)-one-4-carboxylate. From the structures of its derivatives, the similarity of its UV spectrum to those of 1-cinnamylideneindene and 1-crotonylideneindene (orange oil, C₁₃H₁₂, b_0.05 90°; picrate, orange needles, m. 90-90.5°) and the lack of allene group absorption bands in its IR spectrum, I must be a fulvene derivative, Me 7-crotonylidenecyclopenta[c]pyran-1(7H)-one-4-carboxylate.

Helvetica Chimica Acta published new progress about 3115-28-4. 3115-28-4 belongs to catalysis-chemistry, auxiliary class Aliphatic Chain, name is 2-Butylhexanoic acid, and the molecular formula is C10H20O2, Computed Properties of 3115-28-4.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia