[94348-51-3]  · C14H19BSe  · 9-Phenylseleno-9-borabicyclo[3.3.1]nonane  · (MW 277.10)

(reagent for nucleophilic phenylselenylation of enones)

Preparative Methods: stock solutions of this reagent can be prepared by heating equimolar amounts of Benzeneselenol and 9-Borabicyclo[3.3.1]nonane in toluene at 60 °C for 5 h. Stock solutions are stable indefinitely when stored at -20 °C in the dark.1

Handling, Storage, and Precautions: use in a fume hood.

Crossed Aldol Condensations.

This reagent has been found to add to a variety of cyclic and acyclic a,b-unsaturated ketones to give the corresponding b-phenylselenoboron enolates. These species condense in situ with aldehydes to provide the corresponding unsaturated aldol adducts and aldol acetates after oxidative workup and acetylation (eq 1).1 It was subsequently found that dimethyl(phenylseleno)aluminum2 was, in general, a superior reagent for effecting this3 and related2 transformations. In this connection, the latter reagent would appear more effective than dimethyl(phenylthio)aluminum.4

Related Reagents.

Diisobutylaluminum Phenyl Selenide; Dimethylaluminum Methylselenolate; Phenyl Trimethylsilyl Selenide; Tris(phenylseleno)borane.

1. Leonard, W. R.; Livinghouse, T. JOC 1985, 50, 730.
2. Leonard, W. R.; Livinghouse, T. TL 1985, 26, 6431.
3. Leonard, W. R.; Livinghouse, T. unpublished observations.
4. Itoh, A.; Ozawa, S.; Oshima, K.; Nozaki, H. BCJ 1981, 54, 274.

Tom Livinghouse

Montana State University, Bozeman, MT, USA

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