โ Scribed by H.J. Cristau; M. Taillefer
No coin nor oath required. For personal study only.
In order to further delimit the scope of application of diphenylphosphonium diylides, their reactivity towards carbonic acid derivatives was investigated. Non-stabilized diyfides react with ethyl carbonate to give new monoylide intermediates which lead, by in situ Wittig reaction with carbonyl compounds, to the synthesis of ct,ffunsaturated esters or acids the double bond being di-or trisubstituted. The reaction proceeds in mild conditions and with high E stereoselectivity. Stabilized diylides are inactive towards carbonates but semi-stabilized diylides react with ethyl carbonate leading to the synthesis of non-functionalized alkenes instead of the ct,15-unsaturated esters or acids.
๐ SIMILAR VOLUMES
Lithiam diphenylphosphoniam diylides readily attack phenyliscqunate and dic~lohexykarixniiimide The formed stmi-stabilised ylides bear a metallated amide or amidinefunction llwir ase in situ as Wutig reagents towar& aldehydes and ketones is shown to be a new one-pot, E-stereosekctiw synthesis for a,
Tert-butoxyl radicals react with indole and methyl substituted derivatives by hydrogen abstraction. For those compounds which are unsubstituted at the N-atom, hydrogen abstraction takes place almost exclusively at the N-H bond. The reactivity of these compounds correlates with their donor electron c