4-Dimethylaminophenylglyoxal hydrate → 4-(Dimethylamino)phenylglyoxal

HRID 34725Notes

Reaction equation

HRID 34725 reaction equation
O.[CH3:2][N:3]([CH3:14])[C:4]1[CH:9]=[CH:8][C:7]([C:10]([CH:12]=[O:13])=[O:11])=[CH:6][CH:5]=1>C1C=CC=CC=1>[CH3:2][N:3]([CH3:14])[C:4]1[CH:5]=[CH:6][C:7]([C:10]([CH:12]=[O:13])=[O:11])=[CH:8][CH:9]=1

Participants

3

Reactant 1

HCID 212985064-Dimethylaminophenylglyoxal hydrate

Product 1

HCID 212985074-(Dimethylamino)phenylglyoxal

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Procedure

(4-Dimethylaminophenyl)glyoxal monohydrate (3.5 g., 0.018 mol), prepared according to Preparation 22 below, was dissolved in 150 ml. benzene and refluxed for 18 hours (employing a Dean-Stark trap to remove water), stripped to solids, taken up in 50 ml. dry THF, further dried over molecular sieves, and filtered to yield anhydrous (4-dimethylaminophenyl)glyoxal, 0.18 mol, in 50 ml. THF. The latter was reacted with allyl 6,6-dibromopenicillanate (7.82 g., 0.019 mol) and methylmagnesium bromide according to the method of Example A2 to yield chromatographed title product as mixture of diastereoisomers (R and S in the sidechain, unspecified at the 6-position), oil, 2.15 g.,; 1H-nmr 1.42 and 1.50 (2s, 3H), 1.63 (s, 3H), 3.11 (s, 6H), 4.05 (m, 1H), 4.40 and 4.60 (2s, 1H), 4.72 (m, 2H), 5.50 (m, 3H), 5.87 (s, 1H), 5.95 (m, 1H), 6.70 (m, 2H), 7.95 (m, 2H).

Workup

  1. customaccording to Preparation 22 below,
  2. dissolutionwas dissolved in 150 ml
  3. customto remove water),
  4. dry with materialdry THF, further dried over molecular sieves
  5. filtrationfiltered

Sources & evidence

ORD record
ord-3586395442cd413bb7c8e3cdf27a1a22
Source dataset
uspto-grants-1988_08
Patent number
US04762921

Reaction notes

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