Print version Print setup

Syn-dioxygenation of 7-methoxy-4-methyl-1,2-dihydronaphthalene ; 7-Methoxy-2,2,9b-trimethyl-3a,4,5,9b-tetrahydronaphtho[1,2-d][1,3]dioxole

SyntheticPage 785
DOI: 10.1039/SP785
Submitted Jun 09, 2015, published Jun 28, 2015
Ravindra Phatake (ravirajphatake@gmail.com)
A contribution from Dr. C V Ramana's research group


			Reaction Scheme: <IMG src="/images/empty.gif">Syn-dioxygenation of <SPAN id=csm1437666955456 class=csm-chemical-name title=7-methoxy-4-methyl-1,2-dihydronaphthalene grpid="2">7-methoxy-4-methyl-1,2-dihydronaphthalene</SPAN>&nbsp;<IMG src="/images/empty.gif">

Chemicals Used

Oxone (2KHSO5.KHSO4.K2SO4)
Sodium bicarbonate (NaHCO3)
Acetone
Ethyl acetate
Water 

Procedure

To a solution of 7-methoxy-4-methyl-1,2-dihydronaphthalene (100 mg, 0.57 mmol) in acetone (2.5 mL) were added ethyl acetate (0.5 mL), water (0.5 mL) and solid NaHCO3 (145 mg, 1.72 mmol) and the reaction mixture was stirred for 10 min. To this was added solid Oxone (706 mg, 1.15 mmol) and contents were stirred at room temperature for 8 h. After completion of the reaction, the excess acetone evaporated under reduced pressure and remaining reaction mixture portioned between water and ethyl acetate (20 mL each). The organic layer was separated and the aqueous layer extracted with ethyl acetate (2 x 20 mL). Combined organic layer was dried (Na2SO4) and concentrated under reduced pressure. The crude product was purified by silica gel column (ethyl acetate and pet ether as eluent) to afford the 7-Methoxy-2,2,9b-trimethyl-3a,4,5,9b-tetrahydronaphtho[1,2-d][1,3]dioxole (101 mg, 71%) as colourless liquid.

Author's Comments

The reaction seems to be ideal for both large and small scale (5 g- 25mg).
Other benzo-fused olefins like substituted indenes and dihydronaphthalenes work very well.
Reaction condition tolerates different function groups like -Chloro, -Bromo, -azides, etc. 
Other than benzo-fused olefins epoxidation is the main event.  

Data

1H NMR (500 MHz, CDCl3): δ = 0.97 (s, 3H), 1.41 (s, 3H), 1.54 (s, 3H), 1.94 (td, J  = 5.0, 13.4 Hz, 1H), 2.25 (d, J  = 13.4 Hz , 1H), 2.58 (dd, J = 5.0, 16.4 Hz, 1H), 3.06 (ddt, J = 5.0, 12.2 Hz, 1H), 3.77 (s, 3H), 4.13 (m, 1H), 6.56 (s, 1H), 6.79 (d, J = 8.5 Hz, 1H), 7.30 (d, J = 8.5 Hz 1H); 13C-NMR (125 MHz, CDCl3): δ = 24.1 (CH2), 24.3 (CH2), 27.3 (3CH3), 55.12 (CH3), 79.0 (C), 79.1 (CH), 107.8 (C), 112.0 (CH), 113.1 (CH), 129.1 (CH), 132.7 (C), 136.5 (C), 158.3 (C) ppm; GC-HRMS (+EI): calcd. for C15H20O3+ 248.1407, found 248.1425.


Lead Reference

Phatake, R. S.; Ramana, C. V. Tetrahedron Lett. 2015, 56, 2183-2186. (http://dx.doi.org/10.1016/j.tetlet.2015.03.022)
 

Supplementary Information

H1.gif.tif
13C.gif.tif
DEPT.tif

This page has been viewed approximately 11381 times since records began.

Get structure file (.cdx, .sk2, .mol)

Keywords: alkenes, hydroxylation, oxidation, Oxone

Post new comment
Loading ...