Triethylamine → Racemic pivaloyloxymethyl 3-(3,4-dihydroxyphenyl)-2-methylalaninate hydrochloride

HRID 1576878ノート

反応式

HRID 1576878 の反応式
C([NH:11][C@:12]([CH3:25])([C:22]([OH:24])=[O:23])[CH2:13][C:14]1[CH:19]=[CH:18][C:17]([OH:20])=[C:16]([OH:21])[CH:15]=1)(OCC1C=CC=CC=1)=O.[CH2:26](N(CC)CC)C.[Cl:33]C[CH2:35][C:36]([CH3:41])([CH3:40])[C:37]([O-:39])=[O:38]>CN(C)C=O>[ClH:33].[OH:21][C:16]1[CH:15]=[C:14]([CH2:13][C@@:12]([CH3:25])([C:22]([O:24][CH2:26][O:39][C:37](=[O:38])[C:36]([CH3:41])([CH3:40])[CH3:35])=[O:23])[NH2:11])[CH:19]=[CH:18][C:17]=1[OH:20]

参加物

5

反応物 3

HCID 8471TriethylamineHCID 18595367(2S)-2-{[(benzyloxy)carbonyl]amino}-3-(3,4-dihydroxyphenyl)-2-methylpropanoic acidHCID 217530474-Chloro-2,2-dimethylbutanoate

生成物 1

HCID 12439694Racemic pivaloyloxymethyl 3-(3,4-dihydroxyphenyl)-2-methylalaninate hydrochloride

試薬・触媒・溶媒 1

HCID 6228Dimethylformamide溶媒

実験手順

A solution of 4.2 g. (0.012 mole) of racemic N-carbobenzyloxy-3-(3,4-dihydroxyphenyl)-2-methylalanine, 1.3 g. (0.013 mole) of triethylamine and 1.26 g. (0.013 mole) of chloromethylpivalate in 20 ml. dimethylformamide is stirred at 90°C. for 20 hours and then poured into 200 ml. The product is extracted into 100 ml. of ethyl acetate and washed with 25 ml. of a saturated sodium bicarbonate solution and 25 ml. of water. After drying over anhydrous magnesium sulfate and filtering, the filtrate is concentrated under reduced pressure to give the N-carbobenzyloxy derivative of the desired ester. This material is dissolved in 100 ml. of absolute ethanol containing 10 ml. of a 9.6 N ethanolic-anhydrous hydrogen chloride solution and hydrogenated with 3 g. of a 10% palladium-on-carbon catalyst at an initial pressure of 35 p.s.i. for 24 hours. After removing catalyst by filtration, the filtrate is concentrated under reduced pressure. The residue is dissolved in 25 ml. of water, made basic with a saturated sodium carbonate solution to pH 8 and the insoluble product extracted with 100 ml. of ethyl acetate. After drying over anhydrous magnesium sulfate and filtering, 5 ml. of 9.6 N ethanolic anhydrous hydrogen chloride solution is added and the solution concentrated under reduced pressure to given 1.5 g. (22.6%) of the hydrochloride of the racemic pivaloyloxymethyl 3-(3,4-dihydroxyphenyl)-2-methylalaninate, homogeneous upon thin layer chromatography [fluorescent silica gel plate developed with a 5-2-3 (by volume) mixture of n-butanol-acetic acid-water] Rf = 0.86.

後処理

  1. additionpoured into 200 ml
  2. extractionThe product is extracted into 100 ml
  3. washof ethyl acetate and washed with 25 ml
  4. dry with materialAfter drying over anhydrous magnesium sulfate
  5. filtrationfiltering
  6. concentrationthe filtrate is concentrated under reduced pressure

出典と根拠

ORDレコード
ord-ea35afb2f7ac4579bfbcc09e10bdddcd
出典データセット
uspto-grants-1976_09
特許番号
US03983138

反応ノート

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