Trapping Phosphorus Ylides with a Ketone Bound to the Solid Phase

Trapping Phosphorus Ylides with a Ketone Bound to the Solid Phase 

To a solution of (518) (94 mg, 180 mmol) in dry THE (0.9 mL) was added n-BuLi (1.15 M in toluene, 0.11 mL, 170 mmol) at-78 °C under Ar. The deep red solution was immediately added via a cannula to a polymer-supported ketone, such as the CD-ring fragment of Vitamin D3 (517) at -40 °C. The reaction mixture was allowed to gradually warm up to -10 °C and was then filtered and washed in the following way  

Michael Acceptor on Solid Phase (Route to 3,4,6-Trisubstituted Pyrid-2-ones) 

Solid phase N-Acyliminium Ions, Imines and Glyoxylate Chemistry 

Since the seminal paper of Speckamp and Hiemstra [390], N-acyliminium ion species emerged as being among the most versatile of intermediates in the creation of new carbon-carbon bonds. The broad spectrum of reactivity of N-acylimin-ium ions toward different carbon nucleophiles, as well as their ability to participate as both dienophiles and electron-deficient heterodienes in cycloaddition reactions, has made them attractive potential solid-phase intermediates, allowing the generation of chemical diversity starting from a common precursor. 

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