Reaktion #87857

Reaktionsgleichung

DIEA

DMAP

diisopropylethylamine

dimethylamino pyridine

acetyl chloride

acetic anhydride

acetyl chloride

→

isopropyl acetate

sec-butyl acetate

Lösungsmittel

butyl acetate

ethyl acetate

methylene chloride

methylene chloride

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeequipped with a JW1 DB624 column with dimensions of 30 m×250μ×1.4μ
2. 2
   SonstigeThe method ran at 1 ml/min flow, with oven
3. 3
   Sonstigeat 40° C.
4. 4
   Sonstigefor the first two minutes
5. 5
   Sonstigefollowed by temperature ramp at 10° C./min to a temperature of 240° C. which
6. 6
   workup.WAITThe solvent delay was set at 5 minutes
7. 7
   Sonstigewas 180° C.
8. 8
   Sonstigewas 150° C.
9. 9
   Sonstigewas 150° C.
10. 10
    Sonstigesample valve temperature was 105° C.
11. 11
    workup.WAITAfter standing for 30 minutes

Vorschrift

Samples were analyzed on a Agilent 6890 5973 GCMS system equipped with a JW1 DB624 column with dimensions of 30 m×250μ×1.4μ. The method ran at 1 ml/min flow, with oven temperature at 40° C. for the first two minutes followed by temperature ramp at 10° C./min to a temperature of 240° C. which was held for 10 minutes. The solvent delay was set at 5 minutes. Chemical identities of compounds were confirmed by mass spectroscopic qualitative analysis on GCMS against a NIST 2011 library as well as by comparison of retention time against commercial standards. Analysis of samples with volatile alcohols was done on a Gowmac GC system using a Hayesep Q column with He and nitrogen carrier gases. Column temperature was 180° C., detector temp. was 150° C., injector temperature was 150° C., sample valve temperature was 105° C. detector current was 107 mA and injection volume was 1 microliter. Gas samples were analyzed on Varian Micro-GC instruments. Additionally, some product mixtures were analyzed for presence of lower alcohols by derivatizing the alcohol mixture by dissolving in methylene chloride, adding excess of diisopropylethylamine (DIEA), dimethylamino pyridine (DMAP) and acetyl chloride or acetic anhydride. After standing for 30 minutes the reaction mixture was analyzed by GCMS. An experiment for lower molecular weight alcohol analysis was done as follows: The liquid product (30 μl) of the reaction was dissolved in 1 ml of methylene chloride, DIEA was added with a 10 μl syringe in increments until the medium was basic, 2 mg of DMAP was added followed by acetyl chloride. The solution was allowed to stand for about a half hour until the alcohols were esterified to their acetyl derivatives. The resulting mixture was analyzed on the GCMS giving a mixture with ethyl acetate, isopropyl acetate, butyl acetate and sec-butyl acetate. These values represented the approximate percentages of ethyl, isopropyl, butyl alcohols in a sample.

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