Benzocaine → Ethyl 4-hydrazinylbenzoate hydrochloride

HRID 1613620

反応式

HRID 1613620 の反応式
[NH2:1][C:2]1[CH:12]=[CH:11][C:5]([C:6]([O:8][CH2:9][CH3:10])=[O:7])=[CH:4][CH:3]=1.[N:13]([O-])=O.[Na+].O.O.[Sn](Cl)[Cl:20]>Cl.O>[ClH:20].[C:6]([C:5]1[CH:4]=[CH:3][C:2]([NH:1][NH2:13])=[CH:12][CH:11]=1)([O:8][CH2:9][CH3:10])=[O:7]

参加物

6

反応物 3

HCID 2337BenzocaineHCID 61436Stannous chloride dihydrateHCID 23668193Sodium Nitrite

生成物 1

HCID 12414202Ethyl 4-hydrazinylbenzoate hydrochloride収率 20,142.801%

試薬・触媒・溶媒 2

HCID 313Hydrochloric Acid溶媒2 回HCID 962Water溶媒

反応条件

温度
-13 °C

実験手順

To a cooled (-13° C.) and stirred suspension of ethyl 4-aminobenzoate (100 g, 605.3 mmol) in concentrated hydrochloric acid (780 ml) was added dropwise a solution of sodium nitrite (43.9 g, 635.9 mmol) in water (312 ml) at such a rate as to keep the temperature below -4° C. (ca 50 minutes). After being stirred for further 10 minutes at -5° C., the mixture was quickly filtered to remove solids and the clear yellow filtrate was added portionwise to a cooled (-20° C.) and stirred solution of tin (II) chloride dihydrate (682.9 g, 3.02 mmol) in concentrated hydrochloric acid (470 ml) at such a rate as to maintain the temperature below -10° C. (ca 25 minutes). The resulting mixture was allowed to warm to -5° C. over 25 min and the solid was collected by filtration, washed with diethyl ether (2×300 ml) and dried over phosphorous pentoxide-potassium hydroxide at 60° C. in vacuum oven to give 131.8 g (100%) of the title compound as a white solid. A sample recrystallized from absolute ethanol showed: mp 208°-212° C. (needles); δH (360 MHz, DMSO-d6) 10.42 (3H, br s, --N+H3), 8.92 (1H, br s, --NH--), 7.86 (2H, d, J=8.8 Hz, Ar-H), 7.01 (2H, d, J=8.8 Hz, Ar-H), 4.26 (2H, q, J=7.1 Hz, --OCH2 --), 1.30 (3H, t, J=7.1 Hz, --CH3); m/z (CI) 181 (M+ +1).

後処理

  1. customthe temperature below -4° C. (ca 50 minutes)
  2. stirringAfter being stirred for further 10 minutes at -5° C.
  3. filtrationthe mixture was quickly filtered
  4. customto remove solids
  5. additionthe clear yellow filtrate was added portionwise to
  6. temperaturea cooled (-20° C.)
  7. temperatureto maintain the temperature below -10° C. (ca 25 minutes)
  8. temperatureto warm to -5° C. over 25 min
  9. filtrationthe solid was collected by filtration
  10. washwashed with diethyl ether (2×300 ml)
  11. dry with materialdried over phosphorous pentoxide-potassium hydroxide at 60° C. in vacuum oven

出典と根拠

ORDレコード
ord-671cc6765c6b483ebc2f279f18951a4f
出典データセット
uspto-grants-1993_03
特許番号
US05194440

関連ノート

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