Phosphoric Acid → 3,4-Dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-1-benzopyran-2-carbonitrile

HRID 2286823Notes

Reaction equation

HRID 2286823 reaction equation
C(OC1C(C)=CC(O)=C(C)C=1C)(=O)C.CC(O)(C#N)C=C.P(=O)(O)(O)O.B(F)(F)F.C([O:34][C:35]1[C:36]([CH3:50])=[C:37]2[C:42](=[C:43]([CH3:46])[C:44]=1[CH3:45])[O:41][C:40]([CH3:49])([C:47]#[N:48])[CH2:39][CH2:38]2)(=O)C>>[OH:34][C:35]1[C:36]([CH3:50])=[C:37]2[C:42](=[C:43]([CH3:46])[C:44]=1[CH3:45])[O:41][C:40]([CH3:49])([C:47]#[N:48])[CH2:39][CH2:38]2

Participants

6

Reactant 5

HCID 1004Phosphoric AcidHCID 6356Boron trifluorideHCID 1190244-Hydroxy-2,3,6-trimethylphenyl acetateHCID 144156756-Acetoxy-2,5,7,8-tetramethyl-2-cyanochromaneHCID 23317073Methylvinyl ketone cyanohydrin

Product 1

HCID 116802373,4-Dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-1-benzopyran-2-carbonitrileYield 15%

Procedure

Using the method described in Example 1, last paragraph, 25.0 g (0.129 mole) of 4-acetoxy-2,3,5-trimethylphenol were reacted with 12.3 g (0.129 mole) of methyl vinyl ketone cyanohydrin, stabilized with phosphoric acid, and with 13.3 g (0.129 mole) of BF3. Conventional working up of the reaction mixture gave, according to analysis by gas chromatography, 25% of 6-acetoxy-2,5,7,8-tetramethyl-2-cyanochromane; colorless crystals, melting point 149°-151° C. In addition, 15% of 6-hydroxy-2,5,7,8-tetramethyl-2-cyanochromane were obtained.

Workup

  1. customgave

Sources & evidence

ORD record
ord-1dc89288a4c74d72b98ee03e5df95ad9
Source dataset
uspto-grants-1981_05
Patent number
US04268446

Reaction notes

Loading…