Hydrochloric Acid → rac-2-chloro-3,4-dihydro-2,5,7,8-tetramethyl-6-(phenylmethoxy)-2H-1-benzopyran

HRID 621745Notes

Reaction equation

HRID 621745 reaction equation
CO[C:3]1([CH3:24])[CH2:8][CH2:7][C:6]2[C:9]([CH3:23])=[C:10]([O:15][CH2:16][C:17]3[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=3)[C:11]([CH3:14])=[C:12]([CH3:13])[C:5]=2[O:4]1.[Cl-:25].[Ca+2].[Cl-].CCCCCC.Cl>C(OCC)C>[Cl:25][C:3]1([CH3:24])[CH2:8][CH2:7][C:6]2[C:9]([CH3:23])=[C:10]([O:15][CH2:16][C:17]3[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=3)[C:11]([CH3:14])=[C:12]([CH3:13])[C:5]=2[O:4]1

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 8058HexaneHCID 5284359Calcium ChlorideHCID 14415660(+/-)-6-Benzyloxy-2-methoxy-2,5,7,8-tetramethylchroman

Product 1

HCID 10246109rac-2-chloro-3,4-dihydro-2,5,7,8-tetramethyl-6-(phenylmethoxy)-2H-1-benzopyranYield 100.6%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Procedure

A mixture of 10 g of rac-2-methoxy-3,4-dihydro-2,5,7,8-tetramethyl-6-(phenylmethoxy)-2H-1-benzopyran, 10 g of calcium chloride, 100 ml of hexane and 50 ml of diethyl ether was stirred at -5° to -10° C. while HCl gas was bubbled in for 1 hr. An additional 10 g of calcium chloride was added and stirring was continued at room temperature for 2 hr. The mixture was filtered and the filtrate was concentrated in vacuo giving 10.2 g of title product as a light-brown oil. Proton NMR analysis revealed that this product consisted of 66% of the title compound and 33% of the starting 2-methoxy chroman.

Workup

  1. customwas bubbled in for 1 hr
  2. additionAn additional 10 g of calcium chloride was added
  3. filtrationThe mixture was filtered
  4. concentrationthe filtrate was concentrated in vacuo

Sources & evidence

ORD record
ord-af146e2807f14668a5469198bd1218d5
Source dataset
uspto-grants-1989_04
Patent number
US04824971

Reaction notes

Loading…