(η5,η5-1S,2R,4S,5R-1,4-Bis(indenyl)-2,5-diisopropylcyclohexane)titanium Dichloride

Abstract

[139561-09-4] C30H34Cl2Ti (MW 513.38) InChI = 1S/C30H34.2ClH.Ti/c1-19(2)27-17-30(26-16-14-22-10-6-8-12-24(22)26)28(20(3)4)18-29(27)25-15-13-21-9-5-7-11-23(21)25;;;/h5-16,19-20,27-30H,17-18H2,1-4H3;2*1H;/q;;;+2/p-2/t27-,28-,29+,30+;;;/m1.../s1 InChIKey = BNHNXPSWMLMHLK-LYUSHGQQSA-L (alkene isomerization; titanium;4 ansa-bis(indenyl) ligand; chiral ligand; C2 symmetric ligand; asymmetric catalysis8910) Physical Data: mp 264–265 °C (dec 240 °C); d 1.339 g cm−3. Dark green crystals from hexane–CH2Cl2. [α]23D = +2900° (c 0.0202, CH2Cl2). Solubility: sol CHCl3 and CH2Cl2; insol hexane. Preparative Methods: 1 the enantiomerically pure, chiral ligand 2 is prepared in two steps from the known (1S,2R,4S,5R)-2,5-diisopropylcyclohexane-1,4-diol 3 (eq 1).2, 3 It is obtained in 60% yield as a mixture of alkene regioisomers. The chiral titanocene reagent 1 is prepared by treatment of 2 with 2 equiv of n-Butyllithium followed by reaction with Titanium(III) Chloride and subsequent oxidation (HCl/air in CHCl3) of the product (eq 2). It is obtained in 80% yield as a single stereoisomer. (1) (2)