Reaktion #70774

Reaktionsgleichung

EtOAc

sodium borohydride

EtOAc

ethyl 5-cyano-6-methoxy-4-methylpicolinate

calcium chloride

→

6-(hydroxymethyl)-2-methoxy-4-methylnicotinonitrile

Ausbeute 93.0%

Lösungsmittel

CH2Cl2

tetrahydrofuran

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeformed
2. 2
   workup.STIRRINGthe reaction stirred for 1 hr
3. 3
   FiltrationThe suspension was filtered through a pad of Celite
4. 4
   Waschenwashed with EtOAc
5. 5
   SonstigeThe filtrate was transferred to a separatory funnel
6. 6
   Waschenwashed with aq. NH4Cl, brine
7. 7
   Trocknendried (Na2SO4)
8. 8
   Filtrationfiltered
9. 9
   Einengenconcentrated under vacuum
10. 10
    SonstigePurification by silica gel chromatography (Analogix

Vorschrift

To a stirred suspension of ethyl 5-cyano-6-methoxy-4-methylpicolinate (5.0 g, 22.70 mmol) and calcium chloride (10 g, 90 mmol) in tetrahydrofuran (50 mL) and ethanol (50.0 mL) at 0° C. in an ice bath was added sodium borohydride (2.5 g, 66.1 mmol). The reaction was slowly allowed to warm to RT and stirred for 18 hr. A large amount of ppt. formed and LCMS showed that the reaction was complete. An equal volume of EtOAc was added and the reaction stirred for 1 hr. The suspension was filtered through a pad of Celite and washed with EtOAc. The filtrate was transferred to a separatory funnel, washed with aq. NH4Cl, brine, dried (Na2SO4), filtered and concentrated under vacuum. Purification by silica gel chromatography (Analogix, SF40-120 g, 0 to 30% EtOAc in CH2Cl2) gave the product 6-(hydroxymethyl)-2-methoxy-4-methylnicotinonitrile (3.75 g, 21.05 mmol, 93% yield) as a white solid. 1H NMR (400 MHz, DMSO-d6) δ 7.16 (s, 1H), 5.61 (t, J=5.8 Hz, 1H), 4.51 (d, J=5.8 Hz, 2H), 3.94 (s, 3H), 2.47 (s, 3H). MS (ES)+m/e 179.1 [M+H]+.

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