反応 #1483089

反応方程式

DDAIP

4

dodecyl 2-(dimethylamino)propanoate

maleic acid

→

dodecyl 2-(dimethylamino)propanoate maleate salt

収率 98.6%

溶媒

methanol

反応条件

後処理

1. 1
   workup.ADDITIONAfter addition
2. 2
   濃縮The reaction mixture was concentrated under vacuum
3. 3
   その他flushed with ethyl acetate (2×100 mL)
4. 4
   workup.STIRRINGstirred at RT for ½ h (No solid)
5. 5
   濃縮The reaction mixture was concentrated under vacuum
6. 6
   workup.WAITThe obtained sticky solid was kept in deep freezer for 2 h

実験手順

A stirred solution of DDAIP base 4 (80 g, 280 mmol) in methanol (600 mL) was cooled to 0° C., then maleic acid 16 (32.48 g, 280 mmol) was added in one lot. After addition, the temperature of the reaction mixture was slowly raised to RT and stirred at RT for 12 h; the reaction mixture was monitored by TLC. The reaction mixture was concentrated under vacuum and flushed with ethyl acetate (2×100 mL). The obtained residue was taken in n-hexane (200 mL) and stirred at RT for ½ h (No solid). The reaction mixture was concentrated under vacuum. The obtained sticky solid was kept in deep freezer for 2 h to afford dodecyl 2-(dimethylamino)propanoate maleate salt (17, Nex-20) (111 g, yield: 98.6%) as a solid, mp: 65-70° C. 1H-NMR (400 MHz, CDCl3): δ 0.9 (t, 3H), 1.25 (m, 18H), 1.6 (d, 3H), 1.65 (q, 2H), 2.9 (s, 6H), 4.1 (q, 1H), 4.2 (t, 2H), 6.3 (d, 2H); LCMS: 286 (M++1); HPLC: 80.48%.

出典