2385-77-5Relevant articles and documents
Synthesis of Citronellal by RhI-Catalysed Asymmetric Isomerization of N,N-Diethyl-Substituted Geranyl- and Nerylamines or Geraniol and Nerol in the Presence of Chiral Diphosphino Ligands, under Homogeneous and Supported Conditions
Chapuis, Christian,Barthe, Michel,Laumer, Jean-Yves de Saint
, p. 230 - 242 (2001)
For the asymmetric isomerization of geranyl- or neryldiethylamine (( E)- or(Z)-1, resp.) and allyl alcohols geraniol or nerol ((E)- or (Z)-2, resp.) to citronellal (4) in the presence of a [RhI(ligand)cycloocta-1,5-diene)]- catalyst, the atropic ligands 5-11 are compared under homogeneous and polymer-supported conditions with the non-C2-symmetrical diphosphino ferrocene ligands 12-16. The tBu-josiphos ligand 13 or daniphos ligand 19, available in both antipodal series, already catalyse the reaction of (E)-1 at 20 deg (97 percent e.e.) and favourably compare with the binap ligand 5 (see Table 1). Silica-gel- or polymer-supported diphosphino ligands usually afford similar selectivity as compared to the corresponding ligands applied under homogeneous conditions, but are generally less reactive. In this context, a polymer-supported ligand of interest is the polymer-anchored binap (R)-6, in terms of reactivity, selectivity, and recoverability, with a turnover of more than 14400.
Asymmetric cleavage of chiral α,β-ethylenic acetals by organolithium reagents
Alexakis, Alexandre,Mhamdi, Farida,Lagasse, Franz,Mangeney, Pierre
, p. 3343 - 3346 (1996)
,β-Ethylenic chiral acetals react regio- and stereoselectively with organolithium reagents. The obtained enol ether may be hydrolyzed into a chiral β-disubstituted aldehyde.
Multicatalytic approach to one-pot stereoselective synthesis of secondary benzylic alcohols
Casnati, Alessandra,Lichosyt, Dawid,Lainer, Bruno,Veth, Lukas,Dydio, Pawe?
supporting information, p. 3502 - 3506 (2021/05/10)
One-pot procedures bear the potential to rapidly build up molecular complexity without isolation and purification of consecutive intermediates. Here, we report multicatalytic protocols that convert alkenes, unsaturated aliphatic alcohols, and aryl boronic acids into secondary benzylic alcohols with high stereoselectivities (typically >95:5 er) under sequential catalysis that integrates alkene cross-metathesis, isomerization, and nucleophilic addition. Prochiral allylic alcohols can be converted to any stereoisomer of the product with high stereoselectivity (>98:2 er, >20:1 dr).
Method for isomerizing nerol or geraniol to synthesize chiral citronellal from
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Paragraph 0044-0073, (2020/04/29)
The invention provides a method for isomerizing nerol or geraniol to synthesize chiral citronellal, wherein the method comprises the steps: carrying out intramolecular allyl alcohol-aldehyde isomerization reaction on nerol or geraniol under the combined action of a water-soluble metal catalyst and alkali, to obtain the chiral citronellal product with high yield and high enantioselectivity. The method has the main advantages that a water-soluble phosphine ligand and a diamine ligand are combined, a water-soluble catalyst is creatively applied to an isomerization reaction of nerol or geraniol, catalysis is completed under the water-oil two-phase condition, after the reaction is completed, the catalyst is dissolved in a water phase, separation of the catalyst and the product can be achieved through simple phase splitting, repeated recycling of the catalyst can be achieved, and good economic benefits are achieved.
