3,4-dihydro-2H-1-benzopyran-2-carboxylic acid → 2-methyl-3,4-dihydro-2H-1-benzopyran-2-carboxylic acid

HRID 1446384Notes

Reaction equation

HRID 1446384 reaction equation
O1C=CC[CH:2]1C(O)=O.[O:9]1[C:18]2[C:13](=[CH:14][CH:15]=[CH:16][CH:17]=2)[CH2:12][CH2:11][CH:10]1[C:19]([OH:21])=[O:20].CC(C)([O-])C.[K+].C[Si](C)(C)[N-][Si](C)(C)C.[K+]>O1CCCC1>[CH3:2][C:10]1([C:19]([OH:21])=[O:20])[CH2:11][CH2:12][C:13]2[C:18](=[CH:17][CH:16]=[CH:15][CH:14]=2)[O:9]1

Participants

6

Reactant 4

HCID 27236653,4-dihydro-2H-1-benzopyran-2-carboxylic acidHCID 3251421Potassium bis(trimethylsilyl)amideHCID 202775472,3-Dihydrofuran-2-carboxylic acidHCID 23665647Potassium tert-butoxide

Product 1

HCID 219517142-methyl-3,4-dihydro-2H-1-benzopyran-2-carboxylic acid

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

The title compound was prepared following the procedures described for Reference Example 5 substituting 2,3-dihydrofuran-2-carboxylic acid with chromane-2-carboxylic acid at Step A and potassium tert-butoxide in tetrahydrofuran with potassium hexamethyldisilazide (0.5 M in toluene) at Step B. 1H NMR (500 MHz, CD3OD): δ 7.07 (t, 1H), 7.03 (d, 1H), 6.82 (m, 2H), 2.75 (m, 2H), 2.40 (m, 1H), 1.80 (m, 1H), 1.60 (s, 3H).

Sources & evidence

ORD record
ord-da54bf7e5d6749fe97e2a52ac5addac8
Source dataset
uspto-grants-2010_02
Patent number
US07667053B2

Reaction notes

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