Potassium Iodide → 7-iodo-4,4-dimethyl-3,4-dihydronaphthalen-1(2H)-one

HRID 265432Notes

Reaction equation

[CH3:1][C:2]1([CH3:14])[C:11]2[C:6](=[CH:7][C:8](N)=[CH:9][CH:10]=2)[C:5](=[O:13])[CH2:4][CH2:3]1.N([O-])=O.[Na+].[I-:19].[K+]>Cl.O>[CH3:1][C:2]1([CH3:14])[C:11]2[C:6](=[CH:7][C:8]([I:19])=[CH:9][CH:10]=2)[C:5](=[O:13])[CH2:4][CH2:3]1

Participants

Conditions

Temperature: 0 °C

Procedure

To a solution of 4,4-dimethyl-7-amino-1-tetralone (XII) (1.82 g, 10.0 mmol) in concentrated hydrochloric acid (4.69 mL) was added ice cold water (3.13 mL). The reaction mixture was then cooled to 0° C. by use of an ice-salt bath. The reaction mixture was then diazotized by the dropwise addition with stirring of a solution of sodium nitrite (0.76 g, 11.0 mmol) in water (3.13 mL) keeping temperature between 0°-5° C. After stirring for 15 minutes, the reaction mixture was added to a solution of potassium iodide (3.63 g, 21.9 mmol) in water (18.8 mL). After standing for 30 minutes, the dark gum was extracted with ethyl acetate (1×100 mL). The organic phase was then concentrated in vacuo and the residue chromatographed on silica gel (eluted with 5% ethyl acetate in hexane) to give 1.56 g (Y: 54%) of the title product; 1H-NMR (CDCl3): δ 8.33 (d, J=2.0 Hz, 1H), 7.82 (dd, J=8.3, 2.0 Hz, 1H), 7.17 (d, J=8.4 Hz, 1H), 2.72 (t, J=6.8 Hz, 2H), 2.01 (t, J=6.8 Hz, 2H), 1.37 (s, 6H); MS (DCI) m/e: 301 (MH+).

Workup

additionThe reaction mixture was then diazotized by the dropwise addition
custombetween 0°-5° C
waitAfter standing for 30 minutes
extractionthe dark gum was extracted with ethyl acetate (1×100 mL)
concentrationThe organic phase was then concentrated in vacuo
customthe residue chromatographed on silica gel (eluted with 5% ethyl acetate in hexane)

Sources & evidence

ORD record: ord-d4b7de97ee0f4120a43dae45a43d4f99
Source dataset: uspto-grants-1997_07
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05648385

Reaction notes

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