Synthesis and Diels−Alder Reactions of 4-Substituted- 1,3-diphenoxy-2-[(tert-butyldimethylsilyl)oxy]-1,3-butadienes:  Application to the Synthesis of Triaryl Ethers

• Published in: Journal of organic chemistry Vol. 61; no. 17; pp. 5852 - 5856
• Main Authors: Olsen, Richard K, Shao, Rui-lian
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 23.08.1996; Amer Chemical Soc
• Subjects: Chemistry; Chemistry, Organic; Physical Sciences; Science & Technology; DIARYL ETHERS; DERIVATIVES
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo960105d

A novel class of tetrahetero-substituted 1,3-dienes 1a−d having aryl ether substituents at the 1,3-positions were synthesized by enol silylation of 4-substituted 1,3-diphenoxy-3-buten-2-ones 3a−c. The 1Z,3Z configuration of 1b has been assigned by X-ray crystallography. The synthesis of triaryl ethers utilizing a Diels−Alder approach involved reaction of diene 1a with methyl acrylate to furnish a 3:1 mixture of endo- and exo-adducts. Conversion of the adducts to cyclohexenone 8 and aromatization with DDQ gave triaryl ether 9. Cycloaddition reactions of 1a, 1b with some conjugated alkenes exhibited excellent regiospecificity and endo stereoselectivity.