Pentadienyltitaniums as versatile intermediates: regio- and stereo-selectivities
The adduct obtained upon consecutive treatment of 1,4-dienes with butyllithium in the presence of potassium tert-butoxide, chlorotri(isopropyloxy)titanium and a carbonyl compd. contains the a-hydroxyalkyl group invariably and exclusively linked to the 3-position of the former diene. When chlorotri(isopropyloxy)titanium is replaced by the Duthaler-Hafner reagent [(4R,5R)-chloro(cyclopentadienyl)(2,2-dimethyl-a,a,a',a'-tetraphenyl-1,3-dioxolane-4,5-dimethanolato-O,Oa)titanium] the reaction does not only occur regioselectively but also with appreciably high enantioselectivity. [on SciFinder (R)]
2001
Spec. Issue
1016
1018
CAN 135:210607
21-2
General Organic Chemistry
Section de Chimie,Universite, BCh,Lausanne,Switz.
Journal
written in English.
20717-86-6 (Tris(isopropyloxy)titanium chloride); 140438-82-0 Role: CAT (Catalyst use), USES (Uses) (stereoselective and regioselective alkenylation reactions using pentadienyltitaniums as versatile intermediates); 67-64-1 (Acetone); 100-52-7 (Benzaldehyde); 108-94-1 (Cyclohexanone); 123-73-9; 591-93-5 (1,4-Pentadiene); 763-88-2; 923-11-5 (Methyl pyruvate); 5362-50-5; 357979-09-0 Role: RCT (Reactant), RACT (Reactant or reagent) (stereoselective and regioselective alkenylation reactions using pentadienyltitaniums as versatile intermediates); 357979-07-8P; 357979-08-9P Role: RCT (Reactant), SPN (Synthetic preparation), PREP (Preparation), RACT (Reactant or reagent) (stereoselective and regioselective alkenylation reactions using pentadienyltitaniums as versatile intermediates); 10545-00-3P; 21149-19-9P; 357979-04-5P; 357979-05-6P; 357979-06-7P; 358357-49-0P Role: SPN (Synthetic preparation), PREP (Preparation) (stereoselective and regioselective alkenylation reactions using pentadienyltitaniums as versatile intermediates)
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