0 Hits

  • Previous / Next

You are using Science Of Synthesis as a Guest.
Please login to access the full content or check if you have access via Rearrangement of 1-(Alk-1-ynyl)cyclopropanols

DOI: 10.1055/sos-SD-001-00322

Malacria, M.; Aubert, C.; Renaud, J.-L.Science of Synthesis, (20011518.

The rearrangement of 1-(alk-1-ynyl)cyclopropanols 106 to cyclopent-2-en-1-ones proceeds on complexation of their alkynyl part with octacarbonyldicobalt(0) (83).[‌386‌] When the compounds 106 were treated with 1.1 equivalents of complex 83 in tetrahydrofuran at room temperature, complete formation of the corresponding complex occurred. These complexes remained unchanged at room temperature, but, when the solutions were heated to reflux, the corresponding cyclopentenones were obtained in good yields (Scheme 93). The use of ethereal solvents (e.g., THF, DME) generally favored this rearrangement. Various alkynyl substituents (alkyl, aryl, trialkylsilyl) and even those containing functional groups (alkylsulfanyl, tert-butyldimethylsiloxy, hydroxy) can be employed in this reaction.[‌387‌] In the case of the reactions of 1-(alk-1-ynyl)cyclopropanols with an alkyl substituent on the cyclopropane ring, either 4- or 5-substituted cyclopent-2-en-1-ones could be selectively obtained by appropriate choice of stereochemistry and protective group of the substrates (Scheme 93).

Meeeee 88 Meeeeeeeeeeee ee 8-(Mee-8-eeee)eeeeeeeeeeeeee[‌888‌]

Meee eeeeeeeeeeeee eee eeeeeeeeeeee eeeeeee ee eee eeeeeeeeee ee eeeeeeeeeeeeeee ee eeeeeeeeeeee. M eeeeeeeee eeeeeeeee eeeee e eeeeeee eeeeeeeee ee e eeeeee eee eeeeeeee eee ee eee eeeee eeee eeee eeeeeeeeeeeee eeeeee ee eeee. Meee, eeeeeeeee eeeeeeeeee (8888%) eee eeeeeeee ee eeeeeeeee 8888eee% ee eeee(e-eeeeeeeeeeeeeee) eeeeeeeee eee 888eee% ee eeeeeee 88. Mee eeeeeee eeeeeeee eeee eeeeeeeee eeee eee eeeeeeeee ee eeee eeeeeeeeeeeee ee eeeeeee eeeeeee ee eee MeeeeeMeeee eeeeeeeee (Meeeeee; eeeeeee, ee eeeeeeeeeeee eeeeeeeee eeee eee eeee eeeeeeee ee eeeeeeee.

Meeeeeeeeeee Meeeeeeee

Meeeeeeeeeeeee Meeeeeeeeeeee Meeeeeeee ee 8-(Mee-8-eeee)eeeeeeeeeeeeee 888; Meeeeee Meeeeeeee:[‌888‌]

Me e MMM ee MMM eeee (8eM) ee [Me8(MM)8] (88; 8.8eeee) eee eeeee e eeee ee eee 8-(eee-8-eeee)eeeeeeeeeeeee 888 (8eeee) ee MMM ee MMM (88eM) ee ee, eee eeeee eee eeeeeeee eeeeeeeee (ee eeee eeeee, eeeeee 88eee) ee eee eeeeeeeeeeeeeeeeeeee eeeeeee, ee eeeeeeee ee MMM, eee eeeeeee eee eeeeee ee eeeeee eee ee eeeeeeeeeee eeee, eeeee ee eeeee eeeeeeeeee. Meee eee eeeeeeee eee eeeeeeeee ee MMM eee eee ee eee eeeeeeee eee eeeeee ee eee eeeeeeeeeeeee ee eee eeeeee eeeeeee. Meeeeeeeeeee eeeeeeeee eeeeeeeee eeee eeeeeee ee eeeeeeeeee eeeeeee e eeeee eee ee eeeeee eee, eee eeeee eeeeeeeeeeee ee eee eeeee eeeeeee ee eeeeeeeeeee MMM, 8-eeeeeeeeeee eeeeeeeee-8-eeeeee eeee eeeeeeee.