Print version Print setup

​​​​Acid mediated cyclodimerization of styrene oxide to 2-benzyl-4-phenyl-1,3-dioxalane; ​​​​acetal formation

SyntheticPage 312
DOI: 10.1039/SP312
Submitted Jul 10, 2009, published Jul 14, 2009
Ishmael Masesane (
A contribution from Synthetic Group, Botswana

			Reaction Scheme: ​​​​Acid mediated cyclodimerization of styrene oxide to <SPAN class=csm-chemical-name id=csm1268840783711 title=2-benzyl-4-phenyl-1,3-dioxalane grpid="1">2-benzyl-4-phenyl-1,3-dioxalane</SPAN>

Chemicals Used

Styrene (Aldrich), MCPBA (Aldrich) Phosphoric acid (Aldrich)


Phosphoric acid (0.2 ml) was added drop-wise to styrene epoxide (0.5 g, 4.17 mmol) and the mixture was stirred at room temperature for 120 minutes. Saturated sodium bicarbonate (20 ml) was added and the mixture was extracted with dichloromethane (2 x 15 ml) and the organic fractions were combined, dried (magnesium sulphate) and concentrated under reduced pressure. The residue was subjected to flash chromatography eluting with petroleum ether/ethyl acetate (4:1) to give the product as a clear jelly (0.31 g, 61 %).

Author's Comments

All reactions were performed under atmospheric pressure and all reagents were purchased from commercial sources and were used without further purification. The reaction is thought to proceed through a 1,2-hydride shift.


1H NMR (300 MHz, CDCl3): 3.24 (2H, t, J = 5.7, PhCH2), 3.75 (1H, dd, J = 7.8 Hz and 6.3 Hz, H-5), 4.22 (1H, dd, J = 7.8 Hz and 0.9 Hz, H-5), 5.06 (1H, t, J = 6.3 Hz and 0.9 Hz, H-4), 5.38 (1H, t, J = 5.7 Hz, H-2), 7.39-7.44 (10 H, m, Aromatic protons); 13C NMR (75 MHz, CDCl3): 40.8 (PhCH2), 72.0 (C-5), 78.5 (C-4), 105.4 (C-2), 126.4 (C-2'' and C-6''), 126.7 (C-4''), 128.1 (C-1'), 128.3 (C-3'' and C-5''), 128.5 (C-2' and C-6'), 130.0 (C-3' and C-5'), 136.0 (C-1'), 139.4 (C-1'').

Lead Reference

Concellon, J. M.; Bernad, P. L.; de Solar, V.; Garcia-Granda, S.; Diaz, M. R. Adv. Synth. Catal. 2008, 350, 477 doi:10.1002/adsc.200700486

Other References


This page has been viewed approximately 3342 times since records began.

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

Post new comment
Loading ...