Instant ylide
An instant ylid is a ready-made mixture of a phosphonium salt with sodium amide or potassium hydride . Such mixtures were first presented by Manfred Schlosser . This is an improved variant of the Wittig reaction . The finished mixtures are commercially available.
The active Wittig reagent is formed by adding solvents to the instant ylides. Wittig reactions with these reagents are characterized by a high ( Z ) selectivity in the reaction with aldehydes .
literature
- Oleg I. Kolodiazhanyi: " Phosphorous Ylides ", Wiley-VCH, Weinheim, New York, Chichester, Brisbane, Singapore, Toronto, 1999 ISBN 3-527-29531-3 , 393-394.
Individual evidence
- ↑ Bruno Schaub, Gottfried Blaser, Manfred Schlosser: " ω-Hydroxyalkyl-phosphonium salts as" instant-ylid "components: extremely convenient and highly cis-selective synthesis of alkenol-type pheromones " Tetrahedron Letters 1985 , 26 , 307-310 doi : 10.1016 / S0040-4039 (01) 80804-2 .
- ↑ Alexander M. Moiseenkov, Bruno Schaub, Christian Margot, Manfred Schlosser: " A new stereoselective synthesis of (Z) -9-tricosene, the sex attractant of the common housefly " Tetrahedron Letters 1985 , 26 , 305-306 doi : 10.1016 / S0040-4039 (01) 80803-0 .
- ↑ a b Mirella El-Khoury, Qian Wang, Manfred Schlosser: “ A new generation of“ instant ylids ”: Powder mixtures of phosphonium salts and potassium hydride as storable precursors to wittig reagents “ Tetrahedron Letters 1996 , 37 , 9047-9068 doi : 10.1016 / S0040-4039 (96) 02084-9 .