Two new chiral ionic liquids of oxazolinium cations derived from a-pinene: 9,9-Dimethyl-4-propenyl-5-propyl-3 -oxa-5-azonia-tricyclo [6.1.1.0 2,6] dec-4-ene tetrafluoro borate ([ChIPOZ] [BF4]) and 9,9-Dimethyl-4-propenyl-5-propyl-3-oxa-5-azonia-tricyclo [6.1.1.0 2,6] dec-4-ene hexafluoro phosphate ([ChIPOZ][PF6]). Both these chiral ionic liquids have been applied in enantiomeric copper-catalyzed 1,4-addition reactions with diethyl zinc. The enantiomeric excess for product using [ChIPOZ][BF4] is above 70% and for [ChIPOZ][PF6] is above 30%. Chiral ionic liquids worked as phase transfer catalysts In this reaction.
α-Pinene was used as the "chiral pool" in the synthesis of amino alcohol through a two-step reaction, followed by conversion to an oxazoline. Reaction of oxazoline with alkyl bromide gave 9,9-Dimethyl-4-propenyl-5-propyl-3-oxa-5-azonia-tricyclo [6.1. 1.02,6] dec-4-ene bromide ([ChIPOZ][Br]). This organic bromide was used as the starting material for synthesis of chiral ionic liquid. Three additional novel compounds were obtained during the synthesis: But-2-enoic acid (2-hydroxy-2,6,6-trimethyl-bicyclo [3.1.1] hept-3-yl)-amide (Amide), 2,9,9-Trimethyl -4-propenyl -3-oxa -5-aza -tricyclo [6.1.1 .02,6] dec-4-ene (Oxazoline) and 9,9-Dimethyl-4-propenyl-5-propyl-3-oxa-5-azoniatricyclo [6.1.1.02,6] dec-4-ene bromide ([ChIPOZI [Br]).
Products formation in each step of synthesis was confirmed by FT-IR, NMR and Mass Spectrometry analysis.
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