Chemical properties and Preparation methods of 1-PENTANOL, 3-METHYL-5-PHENYL

1-PENTANOL, 3-METHYL-5-PHENYL is an alkyl alcohol compound that exists as a colorless transparent liquid at room temperature and under atmospheric pressure, possessing a fresh floral odor. 1-PENTANOL, 3-METHYL-5-PHENYL exhibits a certain degree of solubility in water and is miscible with most organic solvents. Notably, 1-PENTANOL, 3-METHYL-5-PHENYL displays exceptional fragrance persistence, emanating a natural floral note reminiscent of rose absolute, which has enabled its widespread application in high-end fine fragrances, personal care products, and household cleaning items.

Chemical properties

The chemical transformation characteristics of 1-PENTANOL, 3-METHYL-5-PHENYL are primarily centered on the alcoholic hydroxyl group within its structure. Under the action of suitable oxidizing agents, 1-PENTANOL, 3-METHYL-5-PHENYL can undergo oxidation of the hydroxyl moiety to afford the corresponding aldehyde derivatives. Alternatively, in the presence of a base, 1-PENTANOL, 3-METHYL-5-PHENYL can be converted into the corresponding alkoxide anion, which possesses significant nucleophilicity and can readily participate in nucleophilic substitution reactions with common alkyl halides to produce the corresponding ether derivatives. Furthermore, 1-PENTANOL, 3-METHYL-5-PHENYL can also undergo condensation esterification reactions with carboxylic acid compounds in the presence of dehydrating coupling agents to yield the corresponding ester derivatives.

Preparation methods

Figure1: Preparation methods of 1-PENTANOL, 3-METHYL-5-PHENYL

The reactant (11.9 mg, 47.8 μmol, 0.10 equiv.) was first dissolved in freshly distilled tetrahydrofuran (8 mL per mmol of oxetane) inside a Schlenk tube that had been thoroughly dried by heating under vacuum. To this solution was subsequently added benzylmagnesium bromide (0.85 M in diethyl ether, 130 μL, 111 μmol, 0.22 equiv.), and the resulting mixture was stirred briefly before the introduction of phenylsilane (90 μL, 730 μmol, 1.50 equiv.) and oxetane (89.2 mg, 506 μmol, 1.01 equiv.). The reaction mixture was then allowed to stir at ambient temperature for a period of 24 hours. Following this, additional tetrahydrofuran (40 mL per mmol of oxetane) and an aqueous sodium hydroxide solution (2 M in water, 40 mL per mmol of oxetane) were added, and the biphasic mixture was heated under reflux overnight. After the mixture had cooled to room temperature, the organic and aqueous layers were separated, and the aqueous phase was extracted three times with diethyl ether. The combined organic extracts were then washed with brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. Finally, the resulting crude material was purified by flash column chromatography on silica gel, eluting with a mixture of n-pentane and diethyl ether (7:3), to afford the desired product 1-PENTANOL, 3-METHYL-5-PHENYL.[1]

Substitution reaction

Figure2: Substitution reaction of 1-PENTANOL, 3-METHYL-5-PHENYL

To a dry 100 mL round-bottom flask equipped with a magnetic stirring bar were sequentially added 1-PENTANOL, 3-METHYL-5-PHENYL (1.60 g, 9.0 mmol, 1.0 equiv.), methyl 2-(4-hydroxyphenyl)acetate (1.50 g, 9.0 mmol, 1.0 equiv.), triphenylphosphine (2.36 g, 9.0 mmol, 1.0 equiv.), and anhydrous tetrahydrofuran (23 mL). The resulting solution was then cooled to 0 °C in an ice bath and stirred at that temperature for 20 minutes, after which diisopropyl azodicarboxylate (1.81 g, 9.0 mmol, 1.0 equiv.) was added dropwise with careful maintenance of the internal temperature at or below 0 °C throughout the addition. Following the complete addition, the cooling bath was removed and the reaction mixture was allowed to gradually warm to ambient temperature, where it was stirred for an additional 10 hours. Upon completion, the reaction solution was diluted with dichloromethane (100 mL) and subsequently washed sequentially with 1 N hydrochloric acid (50 mL once), 3 N sodium hydroxide solution (50 mL three times), and brine (50 mL once). The organic phase was then dried over anhydrous sodium sulfate, filtered to remove the drying agent, and concentrated under reduced pressure to afford a crude residue. This residue was finally purified by column chromatography to give the desired product, methyl 2-(4-((3-methyl-5-phenylpentyl)oxy)phenyl)acetate.[2]

Reference

[1] Goli, Harie ; et al, Titanocene-Catalyzed Hydrosilylation of Oxetanes-are Oxetanes the Better Epoxides?  ACS Catalysis (2026), 16(3), 2628-2635.

[2] Shinde, Rupali Dasharath; et al, Cobalt Catalyzed α-Hydroxylation of Arylacetic Acid Equivalents with Dioxygen, Journal of Organic Chemistry (2024), 89(13), 9666-9671.