Hydrochloric Acid → HCID 19068482, compound

HRID 1957766Notes

Reaction equation

HRID 1957766 reaction equation
Cl.[CH:2]1[CH:3]=[CH:4][C:5]([C:8]([OH:18])([C:15]([OH:17])=[O:16])[C:9]2[CH:10]=[CH:11][CH:12]=[CH:13][CH:14]=2)=[CH:6][CH:7]=1.[CH2:19]([O:21]CC)[CH3:20]>>[C:19]([C:6]1[CH:7]=[CH:2][CH:3]=[CH:4][C:5]=1[C:8]([C:9]1[CH:10]=[CH:11][CH:12]=[CH:13][CH:14]=1)([OH:18])[C:15]([OH:17])=[O:16])(=[O:21])[CH3:20]

Participants

4

Reactant 3

HCID 313Hydrochloric AcidHCID 3283Diethyl EtherHCID 6463Benzilic acid

Product 1

HCID 19068482HCID 19068482, compound

Procedure

Acetyl chloride (35 mL, 490 mmol) was added dropwise to a solution of benzilic acid (100 g, 438 mmol) in 300 mL THF over a period of five minutes. The solution was cooled to 0° C. and pyridine (70 mL, 865 mmol) was added dropwise over a period of 30 minutes, during which time a thick white precipitate developed. The ice bath was removed, the reaction flask was equipped with a CaCl2 drying tube and stirred overnight. The next day, the solution was filtered to isolate a white precipitate and the yellow THF supernatant was concentrated to a turbid oil. Most of the product was isolated in the precipitate as the pyridinium acetylbenzilate salt, but some was retained in the supernatant. The precipitate and oil were added to a large separatory funnel charged with 1000 mL diethyl ether and 400 mL of 1.2M HCl. The contents were thoroughly mixed, the aqueous portion separated and discarded. The ether solution was washed twice with 400 mL 1.2M HCl, once with 300 mL saturated NaCl solution, dried over MgSO4, filtered and concentrated to approximately 200 mL. The product was precipitated by addition of 800 mL hexanes, isolated by filtration, and air dried overnight. Yield 88 g (74%). 1H NMR (CDCl3): δ7.1-7.7 (m, 10H ArH), 5.7 (s, 3H, COOH), 2.08 (s, 3H, RO(O)CCH3). This synthesis could be easily modified by one of skill in the art to incorporate a thiol or amino analog of benzylic acid.

Workup

  1. additionThe precipitate and oil were added to a large separatory funnel
  2. additionThe contents were thoroughly mixed
  3. customthe aqueous portion separated
  4. washThe ether solution was washed twice with 400 mL 1.2M HCl, once with 300 mL saturated NaCl solution
  5. dry with materialdried over MgSO4
  6. filtrationfiltered
  7. concentrationconcentrated to approximately 200 mL
  8. customThe product was precipitated by addition of 800 mL hexanes
  9. customisolated by filtration, and air
  10. customdried overnight
  11. customThis synthesis

Sources & evidence

ORD record
ord-6acebd84decc4c81b4add550f74bfedf
Source dataset
uspto-grants-1998_07
Patent number
US05786496

Reaction notes

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