Diastereoselective [4+2] Cycloaddition Reaction of 1-Neomenthyl-1,2-diphosphole: Facile Synthesis of P-Chiral Cage Phosphines

作者：Zagidullin Almaz^*; Miluykov Vasili; Polyancev Fedor; Latypov Shamil; Sinyashin Oleg; Loennecke Peter; Hey Hawkins Evamarie

来源：European Journal of Organic Chemistry, 2015, 2015(24): 5326-5329.

DOI：10.1002/ejoc.201500558

• Asymmetric synthesis
• Diastereoselectivity
• Cycloaddition
• Phosphorus heterocycles
• Chiral phosphanes

3,4,5-Triphenyl-1-(+)-neomenthyl-1,2-diphosphole was obtained by alkylation of sodium 3,4,5-triphenyl-1,2-diphosphacyclopentadienide with (-)-menthyl tosylate. High delocalization within the planar heterocycle of the diphosphole is indicative of low aromaticity. Thus, the [4+2] cycloaddition reaction of this compound with maleic anhydride proceeded under mild conditions with high diastereoselectivity (up to 88% de) and resulted in the corresponding enantiopure 1,7-diphosphanorbornadiene as an individual enantiomer. The observed high diastereoselectivity may be explained by thermodynamic control of the reaction.

• 出版日期2015-8