500000-20-4Relevant articles and documents
Asymmetric catalysis based on chiral phospholanes and hydroxyl phospholanes
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Page column 19, (2010/02/06)
Chiral phosphine ligands derived from chiral natural products including D-mannitol and tartaric acid. The ligands contain one or more 5-membered phospholane rings with multiple chiral centers, and provide high stereoselectivity in asymmetric reactions.
Asymmetric catalysis based on chiral phospholanes and hydroxyl phospholanes
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Example 2, (2010/01/30)
Chiral phosphine ligands derived from chiral natural products including D-mannitol and tartaric acid. The ligands contain one or more 5-membered phospholane rings with multiple chiral centers, and provide high stereoselectivity in asymmetric reactions.
Synthesis of chiral hydroxyl phospholanes from D-mannitol and their use in asymmetric catalytic reactions
Li, Wenge,Zhang, Zhaoguo,Xiao, Dengming,Zhang, Xumu
, p. 3489 - 3496 (2007/10/03)
Chiral hydroxyl monophosphane 3 [(2S,3S,4S,5S)-3,4-dihydroxy-2,5-dimethyl-1-phenylphospholane] and bisphospholanes 5a [1,2-bis[(2S,3S,4S,5S)-3,4-dihydroxy-2,5-dimethylphospholanyl]benzene] and 5b [1,2-bis[(2S,3S,4S,5S)-2,5-diethyl-3,4-dihydroxyphospholanyl]benzene] were synthesized from readily available D-mannitol in high yields. Strategies for protection and deprotection of OH-groups in the presence of phosphines have been explored. Rate acceleration in the Baylis - Hillman reaction was observed when a hydroxyl phosphine was used as the catalyst. Rhodium complexes with chiral bisphospholanes are highly enantioselective catalysts for the asymmetric hydrogenation of various kinds of functionalized olefins such as dehydroamino acid derivatives, itaconic acid derivatives, and enamides. An interesting feature of the hydroxyl phospholane system is that hydrogenation of some substrates can be carried out in water with >99% ee and 100% conversion (e.g., itaconic acid).
Rhodium-hydroxyl bisphospholane catalyzed highly enantioselective hydrogenation of dehydroamino acids and esters
Li, Wenge,Zhang, Zhaoguo,Xiao, Dengming,Zhang, Xumu
, p. 6701 - 6704 (2007/10/03)
A chiral hydroxyl bisphospholane, 1,2-bis[(2S,3S,4S,5S)-3,4-dihydroxyl-2,5-dimethylphospholanyl]benzene (4), was synthesized from readily available D-mannitol. Its Rh(I) complex catalyzes asymmetric hydrogenation of dehydroamino acids and their ester derivatives with excellent enantioselectivities (98 to >99% ee).