Details

Autor(en) / Beteiligte

• Lai, Jingxiong
• Huang, You

Titel

Phosphine-catalyzed formal Buchner [6+1] annulation: construction of cycloheptatrienes

Ist Teil von

• Chemical communications (Cambridge, England), 2023-11, Vol.59 (88), p.13215-13218

Erscheinungsjahr

2023

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• An unprecedented phosphine-catalyzed formal Buchner [6+1] annulation of a newly designed allenoate has been developed, providing a series of cycloheptatriene derivatives in moderate to good yields (up to 99%). This reaction demonstrates that the introduction of an electrophilic allylic group to allenoates effectively extends the reaction scope of phosphine-catalyzed annulation, providing a concise route to cycloheptatrienes. Mechanistic study indicated that this reaction involves a [4+2] Diels-Alder reaction and ring expansion of the bicyclo[4.1.0] moiety, which is similar to the Buchner reaction. Notably, an enantioselective variant of this [6+1] annulation can also be performed using a chiral iminophosphine catalyst. A new method is developed to construct cycloheptatriene derivatives efficiently by phosphine-catalyzed formal Buchner [6+1] annulation of a newly designed allenoate and 4-oxo-4 H -chromene-3-carbaldehydes.