172959-40-9Relevant academic research and scientific papers
Intramolecular Diels-Alder reactions of the retinoid side chain
Shealy, Y. Fulmer,Riordan, James M.,Frye, Jerry L.,Campbell, Sheila R.
, p. 405 - 424 (1996)
Retinyl propynyl ether (RPE) undergoes an intramolecular Diels-Alder reaction to form a tetrahydroisobenzofuran derivative by addition of the alkyne group at positions 11 and 14 of the retinoid side chain. The Diels-Alder product can be isolated after RPE has been heated in refluxing ethanol. The Diels-Alder reaction also occurs very slowly in the solid state at low temperatures. The tetrahydroisobenzofurans is readily dehydrogenated to an aromatic retinoid, a 1,3-dihydroisobenzofuran. 2-Butynyl and 2-propenyl retinyl ethers undergo intramolecular cyclization to similar Diels-Alder products that can be isolated in yields of 50-60% after the ethers have been heated in refluxing toluene.
