2-Methyl-3-ethyl-2,3-pentanediol

Problem 21.17 The insect repellent 6-12 (2-ethyl-l,3-hexanediol) is produced by the same chemical company that produces n-butyl alcohol and 2-ethyl-l-hexanol aiissest a method for its synthesis. How could you synthesize 2-methyl-2,4-pentanediol ... 

With the tetraphenylarsonium cation, the fluoroborate anion forms an ion-pair, which can be extracted with chloroform. Quantitative conversion of boron into BF4, and subsequent quantitative extraction are ensured by using an excess of fluoride (at pH 2-3), and by leaving the solution to react for sufficient time before extraction [7]. Boric acid is often extracted from acidic solutions (1-6 M HCl) with 2-ethyl-1,3-hexanediol in CHCI3 [10-14], with 2,2,4-trimethyl-1,3-pentanediol in CHCI3 [15], or with 2-methyl-2,4-pentanediol in CHCI3 [16] or in MIBK[17]. 

Propanoic acid butyl ester. See n-Bulyl propionate Propanoic acid, ethenyl ester. See Vinyl propionate Propanoic acid ethyl ester. See Ethyl propionate Propanoic acid, 2-hydrorqr-. See Lactic acid Propanoic acid, 2-hydrorqr-, ammonium salt SeeAmmonium lactate Propanoic acid, 2-hydrorqr-, butyl ester. See Butyl lactate Propanoic acid, 2-hydrorqr-, 1-methylethyl ester. See Isopropyl lactate Propanoic acid, 2-methyl-, monoester with 2,2,4-trimethyl-1,3-pentanediol. See2,2,4-Trimethyl-1,3-pentanediol isobutyrate Propanoic acid, pentyl ester. SeeAmyl propionate Propanoic acid, propyl ester. See Propyl propionate Propanoic acid, 3,3 -thiobis-, dioctadecyl ester. See Disteatyl thiodipro-pionate... 

Methyl-2,4-pentanediol 2-(2-ethoxyethoxy)ethyl acetate Nonanol mixed isomers 1,2-Ethanediol... 

Methyl-l,2-pentanediol 3.3- Dimethyl-l,2-butanediol 4.4- Dimethyl-l,2-pentanediol 4- Methyl-l,2-hexanediol 5- Methyl-l,2-hexanediol 2-Methyl-2-propyl-l,3-propanediol 2-Ethyl-2-butyl-l,3-propanediol 2-Butyl-2-methyl-l,3-propanediol 2-Butyl-2-ethyl-l,3-propanediol 2,2-Dibutyl-l,3-propanediol... 

For promoting penetration, the following polyol compounds are suitable (15) 2-Ethyl-2-methyl-l,3-propanediol, 3,3-dimethyl-1,2-butanediol, 2,2-diethyl-l,3-propanediol, 2-ethyl-l,3-hexanediol, and 2,2,4-trimethyl-l,3-pentanediol. Among the above components, preferable examples include 2-ethyl-l,3-hexanediol and 2,2,4-tri-methyl-l,3-pentanediol. 

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