Reaktion #1006197

Reaktionsgleichung

potassium carbonate

3-(tert-butyldimethylsilyloxymethyl)-5-methyl-2,3-dihydrobenzo[1,4]dioxine-6-carboxylic acid N′-tert-butyl hydrazide

ether hexane

3,5-dimethylbenzoyl chloride

→

3,5-dimethylbenzoic acid N-tert-butyl-N′-[3-(tert-butyldimethylsilyloxymethyl)-5-methyl-2,3-dihydrobenzo[1,4]dioxine-6-carbonyl]-hydrazide

Ausbeute 76.0%

Lösungsmittel

ethyl acetate

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeTo a round bottom flask equipped
2. 2
   workup.STIRRINGStirring
3. 3
   Sonstigethe phases separated
4. 4
   WaschenThe organic phase was washed once with water, once with saturated aqueous sodium chloride
5. 5
   Trocknendried over magnesium sulfate
6. 6
   Filtrationfiltered
7. 7
   Sonstigeevaporated
8. 8
   Sonstigechromatographed on silica gel eluting with 20% ether/hexane

Vorschrift

To a round bottom flask equipped with magnetic stirring was added ethyl acetate (7 mL), 25 wt % aqueous potassium carbonate solution (2.03 g, 3.67 mmol), and 3-(tert-butyldimethylsilyloxymethyl)-5-methyl-2,3-dihydrobenzo[1,4]dioxine-6-carboxylic acid N′-tert-butyl hydrazide (0.50 g, 1.22 mmol). To this was added 3,5-dimethylbenzoyl chloride (0.31 g, 1.84 mmol). Stirring was continued for 18 hours. The reaction was diluted with ethyl acetate and the phases separated. The organic phase was washed once with water, once with saturated aqueous sodium chloride, dried over magnesium sulfate, filtered and evaporated. The residue was flash chromatographed on silica gel eluting with 20% ether/hexane, then 50% ether/hexane to give a white solid, 3,5-dimethylbenzoic acid N-tert-butyl-N′-[3-(tert-butyldimethylsilyloxymethyl)-5-methyl-2,3-dihydrobenzo[1,4]dioxine-6-carbonyl]-hydrazide, (0.50 g, 0.92 mmol) in 76% yield. 1H-NMR (300 MHz, CD3COCD3) δ (ppm): 0.10 (s, 6H), 0.90 (s, 9H), 1.59 (s, 9H), 1.89 (s, 3H), 2.25 (s, 6H), 3.92 (m, 2H), 4.05 (m, 1H), 4.22 (m, 1H), 4.34 (m, 1H), 6.33 (d, 1H), 6.56 (d, 1H), 7.02 (s, 1H), 7.13 (s, 2H), 9.49 (s, 1H); TLC: Rf=0.30 (1:1 ether/hexane).

Quelle