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Chiral terpene auxiliaries V: Synthesis of new chiral ?-hydroxyphosphine oxides derived from ?-pinene.

ABSTRACT: New chiral regioisomeric ?-hydroxyphosphine ligands were synthesized from ?-pinene. The key transformation was the thermal [2,3]-sigmatropic rearrangement of allyldiphenylphosphinites, obtained from (1R,2R,4S,5R)-3-methyleneneoisoverbanol and (1R,2R,3R,5R)-4-methyleneneoisopinocampheol, to allylphosphine oxides. Hydroxy groups were introduced stereoselectively through a hydroboration-oxidation reaction proceeding from the less hindered site providing a trans relationship between the hydroxy and the phosphine substituents.

SUBMITTER: Kmieciak A

PROVIDER: S-EPMC6839555 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Chiral terpene auxiliaries V: Synthesis of new chiral γ-hydroxyphosphine oxides derived from α-pinene.

Kmieciak Anna A Krzemiński Marek P MP

Beilstein journal of organic chemistry 20191022

New chiral regioisomeric γ-hydroxyphosphine ligands were synthesized from α-pinene. The key transformation was the thermal [2,3]-sigmatropic rearrangement of allyldiphenylphosphinites, obtained from (1R,2R,4S,5R)-3-methyleneneoisoverbanol and (1R,2R,3R,5R)-4-methyleneneoisopinocampheol, to allylphosphine oxides. Hydroxy groups were introduced stereoselectively through a hydroboration-oxidation reaction proceeding from the less hindered site ...[more]

PMID: 31728163

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