Polymer-supported silyl cyanide and silyl azide: useful reagents for solid-phase applications.
The support of a delicate reagent on a solid matrix allows for better and safer handling of the reagent itself. Because we had an interest in silicon-based supported reagents(1) we turned our attention to a polymer-supported trialkylsilyl cyanide and trialkylsilyl azide starting from a commercially available trialkylsilane resin. The supported cyanide was obtained with excellent yield and proved to be shelf-stable. This supported reagent was reacted with a series of aldehydes and ketones yielding the corresponding polymer-supported cyanohydrins in good-to-excellent yields. A stability study on a model cyanohydrin demonstrated that these supported intermediates also can be stored for a prolonged time. For the last step, a cleavage strategy that could release either cyanohydrins or alpha-hydroxy esters was adopted. Finally, we prepared a polymer-supported trialkylsilyl azide, which also proved to be shelf-stable.
Missio
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GlaxoWellcome Medicines Research Centre, Via Fleming 4, 37135 Verona, Italy. amissio@hrvet.com
Marchioro
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Rossi
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Panunzio
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Selva
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S
Seneci
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P
D000447:Aldehydes / Q000737:chemistry*; D001386:Azides; D003486:Cyanides; D007202:Indicators and Reagents; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure; D009570:Nitriles / Q000138:chemical synthesis* / Q000737:chemistry; D011108:Polymers; D018629:Spectrometry, Mass, Secondary Ion
D000447:Aldehydes; D001386:Azides; D003486:Cyanides; D007202:Indicators and Reagents; D007659:Ketones; D009570:Nitriles; D011108:Polymers