Synthesis of enantiomerically pure divinyl- and diallylcarbinols

Abstract

reactions of organo-metal compounds reactions of organo-metal compounds O 0350 -065Synthesis of Enantiomerically Pure Divinyl-and Diallylcarbinols.-The novel synthesis of enantiomerically pure α-chiral divinyl-and diallylcarbinols involves the treatment of acylated bornane sultams and oxazolidinones with excess of vinyl-or allylmetal compounds. For the preparation of divinylcarbinols, acylated bornane sultams are the starting materials of choice, whereas diallylcarbinols can be prepared from both types of acyl derivatives. The chemoselective formation of derivative (XII) is in particular remarkable since the ester group is not attacked by application of stoichiometric amounts of vinyl metal compound (II). Two examples for the application of the obtained carbinols in metathesis reactions are given, as well as reaction conditions which lead to selective formation of chiral butenones such as (X).

Development of a Phase-Transfer-Catalyzed, [2,3]-Wittig Rearrangement

“…The 1 H NMR spectroscopic data matched that from an analogous compound previously reported in the literature. 57 Preparation of 2-(Allyloxy)-1-tetralone (10). The preparation of 2-(allyloxy)-1-tetralone followed the preparation reported by Mukaiyama with minor changes.…”

New Routes to Chiral Evans Auxiliaries by Enzymatic Desymmetrisation and Resolution Strategies

“…Recrystallisation from n-hexane/ isopropanol afforded rac-3 as a white solid (266.7 mg, 57%); mp 77 ± 79 8C; R f (n-hexane/EtOAc, 10 : 90) 0. 41 …”

The chemistry of the carbon–transition metal double and triple bond: annual survey covering the year 2002

“…9), including: (1) synthesis of five-membered ring oxygen heterocycles (e.g. 97) for nucleoside synthesis [301]; (2) synthesis of 2,5-dihydrofurans [302]; (3) synthesis of an ␣,␤-unsaturated five-membered ring lactone for acaterin total synthesis [303]; (4) synthesis of six-membered ring oxygen heterocycles [304]; (5) synthesis of six-membered ring oxygen heterocycles (e.g. 98) for total synthesis of cascospongiolide B [305]; (6) synthesis of six-membered ring oxygen heterocycles (e.g.…”