A practical synthesis of syn- and anti-α,β-dihydroxyphosphinates via diastereoselective reduction of α-phosphinoyl ketones
摘要:
Reduction of (3-keto-diphenylphosphine oxide (S)-4 derived from (S)-mandelic acid with NaBH4 in methanol at -78 degrees C gave the anti-3-diphenylphosphinoyl-1,2-diol 6, whereas the reduction of (S)-4 with Zn(BH4)(2) in THF at -78 degrees C afforded the syn-1,2-diol 5, both in high yield and excellent diastercoselectivity. This procedure represents a new approach to the diastereoselective synthesis of diphenylphosphinoyl diols and an example of highly diastereoselective 1,2-induction. A theoretical model to explain the direction and degree of asymmetric induction is proposed. (C) 2008 Elsevier Ltd. All rights reserved.
A practical synthesis of syn- and anti-α,β-dihydroxyphosphinates via diastereoselective reduction of α-phosphinoyl ketones
摘要:
Reduction of (3-keto-diphenylphosphine oxide (S)-4 derived from (S)-mandelic acid with NaBH4 in methanol at -78 degrees C gave the anti-3-diphenylphosphinoyl-1,2-diol 6, whereas the reduction of (S)-4 with Zn(BH4)(2) in THF at -78 degrees C afforded the syn-1,2-diol 5, both in high yield and excellent diastercoselectivity. This procedure represents a new approach to the diastereoselective synthesis of diphenylphosphinoyl diols and an example of highly diastereoselective 1,2-induction. A theoretical model to explain the direction and degree of asymmetric induction is proposed. (C) 2008 Elsevier Ltd. All rights reserved.
A practical synthesis of syn- and anti-α,β-dihydroxyphosphinates via diastereoselective reduction of α-phosphinoyl ketones
作者:Haydée Rojas-Cabrera、Julio M. Hernández-Pérez、Minhhuy Hô、Eugenio Hernández-Fernández、Mario Ordóñez
DOI:10.1016/j.tetasy.2007.12.016
日期:2008.2
Reduction of (3-keto-diphenylphosphine oxide (S)-4 derived from (S)-mandelic acid with NaBH4 in methanol at -78 degrees C gave the anti-3-diphenylphosphinoyl-1,2-diol 6, whereas the reduction of (S)-4 with Zn(BH4)(2) in THF at -78 degrees C afforded the syn-1,2-diol 5, both in high yield and excellent diastercoselectivity. This procedure represents a new approach to the diastereoselective synthesis of diphenylphosphinoyl diols and an example of highly diastereoselective 1,2-induction. A theoretical model to explain the direction and degree of asymmetric induction is proposed. (C) 2008 Elsevier Ltd. All rights reserved.