Investigation of the diastereofacial selectivity of the addition of 1-metalated (E)- and (Z)-hept-1-enes to the COREY aldehyde — A comparison between vinyllithium and vinyltitanium compounds1,2

On the Palladium(II)‐Catalysed Oxidative Rearrangement of Propargylic Acetates

“…[1] As a result of our previous success with the [3,3]-sigmatropic palladiumcatalysed rearrangement of allyl acetates, utilised in the stereoselective total synthesis of prostaglandins, [2,3] we have investigated the palladium[II]-mediated oxidative rearrangement of propargylic acetates, using several propargylic acetates to both generalise our findings and to explore the scope of this reaction and to optimise the yields of products. The term ™oxidative∫ for this new rearrangement was introduced by Tsuji.…”

Ti(OiPr)4 in Stereoselective Synthesis

“…A wide range of organometallics react with Ti(OiPr) 4 to form an active organotitanium reagent or titanatespecies [8]. These titanium ate complexes may differ significantly in their stereochemical and regiochemical reactivity from those of their starting organometallics (typical examples for ester/ketone differentiation of an allylmagnesium -titanium ate complex [9] and stereoselectivity of an alkynyl titanium reagent [10] are given in Scheme 2; see also 1,4addition of α,β-unsaturated ketones in the presence of titanium ate complexes [11] Titanium(IV) isopropoxide is a flammable, nontoxic, moisture-sensitive liquid (m.p. 18-20 °C; b.p.…”