Science of Synthesis

Thomas, A. W., Science of Synthesis, (2007) 31, 529.

In the context of preparing diaryl ethers as part of the total synthesis of members of the ellagitannin family,[‌220‌] an unusual reaction of 1,2-quinones was developed into a preparatively useful reaction. The key transformation is the oxophilic union of aryl Grignard reagents with the 1,2-quinone ‌179‌ in the presence of copper(I) iodide or cerium(III) chloride at −90°C to give a >5:1 regiosiomeric mixture of the diaryl ethers ‌180‌ and ‌181‌ in combined yields of 60 and 75%, respectively (‌Scheme 62‌).[‌221‌,‌222‌] When the Grignard reagent derived from 2-bromoanisole is used, the reaction gives 1:1 mixtures of the corresponding regioisomeric diaryl ether products in modest yields.[‌221‌,‌222‌]

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‌Meeeee 88‌ Meeeeeeeeeee ee e 8,8-Meeeeee[‌888‌,‌888‌]

Meeee eeeeeee eeeeeeee eeeeeeeeee, eee 8,8-eeeeeee ‌888‌ ee eeeeeeeee eeee eee eeeeeeeeeeeee eeeeeee eeeeeee ‌888‌ (‌Meeeee 88‌). Meeeeeeeee, eee eeeee eeeeeeeeee ‌888‌ eee eeee ee eeeeeeeee eeee eee eeeeeee eeeeeee ‌888‌ ee e 88% eeeee eeeeeee e eeeeeee eeeeee ee eeeeeeeeeeeeeee (‌Meeeee 88‌).[‌888‌]

‌Meeeee 88‌ Meeeeee Meeeeeeeeeee Meeeeeeee ee 8,8-Meeeeee Meeeeeeeeee[‌888‌]

Meeeeeeeeeee Meeeeeeee

Meeeee 8,8,8-Meee(eeeeeeeee)-8-[8,8-eee(eeeeeeeee)-8-(eeeeeeeeeeeeeee)eeeeeee]eeeeeeee (‌888‌):[‌888‌]

M(MMe)8 (888 ee, 8.88 eeee) eee eeeee ee e eeee ee eee 8,8-eeeeeee ‌888‌ (888 ee, 8.88 eeee) ee MMMe8 (8 eM). Mee eeeeeee eee eeeeee ee 88–88°M (eee-eeee eeeeeeeeeee) eee 88 e, eeee eeeeee, eee eeeeeeee. Mee M(MMe)8 eeeeee eee eeeeee eeee eeee MM8Me8, eee eee eeeeeeee eeeeeeee eee eeeeeeee eeee eeeeeeeeeeee ee eeee e eeeeeee, eeeee eee eeeeeee eeee e eeee ee MeMMe (88 ee, 8.88 eeee) ee MeMM (8 eM). Mee eeeeeee eee eeeeeee eee 8 e eee eeee eeeeeeeeeee eeeeeee MeMMe eee M8M. Mee eeeeeee eeeee eee eeeeeeeee, eeeeee eeee eeeee, eeeee (Me8MM8), eeeeeeee, eee eeeeeeeeeeee ee eeee e eeeeeee, eeeee eee eeeeeeee ee eeeeeeeeeeeeee ee −88°M eeeee eeeee. Mee eeeeeeeee eeeeeee eee eeeeeeeee ee e eeee ee Me8M8M8 (888 ee, 8.88 eeee) ee MMM (8 eM) eee M8M (8 eM) ee 8°M. Meeee 88 eee, eee eeeeeee eee eeeeeeeeeee eeeeeee MeMMe eee M8M, eee eee eeeeeee eeeee eee eeeeeeeee, eeeeee eeee eeeee, eeeee (Me8MM8), eeeeeeee, eee eeeeeeeeeeee. Mee eeeeeee eee eeeeeee eeee MeMe (888 μM, 8.8 eeee), M8MM8 (888 ee, 8.88 eeee), eee MM (88 ee, 8.88 eeee) ee eeeeeee (88 eM). Mee eeeeeeeee eeeeeee eee eeeeeeee eee 88 e, eeeeee, eee eeeeeeee eeeeeee Meeeee. Mee eeeeeeee eee eeeeeeeeeeee eee eeee eeeeeeee ee eeeee eeeeeeeeeeeeee (eeeeee eee, eeeeee/Me8M 8:8) ee eeee e eeeee-eeeee eeee; eeeee: 88 ee (88%).

References