640769-23-9Relevant academic research and scientific papers
Synthesis of a Cn-Cn+6 building block common to important polyol,polyene antibiotics from a divinylcarbinol by a desymmetrizing sharpless epoxidation
Nachbauer, Luc,Brueckner, Reinhard
, p. 6545 - 6562 (2013/11/06)
A stereocontrolled synthesis of the enantiomerically pure epoxide 7b from propargyl ether 15 has been realized in 15 steps. Epoxide 7b represents a building block for the "eastern" moieties of the title compounds. Key steps in our approach were a desymmetrizing Sharpless epoxidation (→a€‰anti,cis-16), the selective processing of the bis-enolate of the bis(tert-butyl alkoxyacetate) 11 through a diastereoselective [2,3]-Wittig rearrangement (→a€‰syn,syn-9), and a stereo- and chemoselective iodolactonization (→a€‰35). The CO2H groups of dicarboxylic acid 37 were differentiated in a one-pot bis-oxidation reaction. The latter entailed the novel transformation of HO2CCH2-O-alkyl into AcOCH2-O-alkyl. The termini of a bis(tert-butyl alkoxyacetate) have been differentiated by forming the bis-enolate and engaging one enolate in a diastereoselective [2,3]-Wittig rearrangement. A diastereo- and chemoselective iodolactonization established the stereocenter of the epoxide ring. Copyright
Stereocomplementary desymmetrizations of divinylcarbinols by zirconium(IV)- vs. titanium(IV)-mediated asymmetric epoxidations
Kramer, Rainer,Berkenbusch, Thilo,Brueckner, Reinhard
supporting information; experimental part, p. 1131 - 1148 (2009/06/17)
Substituted Cs-symmetric penta-1,4-dien-3-ols ("divinylcarbinols") containing cis- or trans-disubstituted C=C bonds were desymmetrized by asymmetric monoepoxidations. Sharpless conditions gave anti-configured monoepoxides. For cis,cis-divinylca
Concise Synthesis of Optically Pure syn-1,3-Diols by Stereoselective Desymmetrization of a Divinylcarbinol
Berkenbusch, Thilo,Brückner, Reinhard
, p. 1813 - 1816 (2007/10/03)
Divinylcarbinols 17 and 18, CS-symmetrical and cis-configured, were desymmetrized by Sharpless' asymmetric epoxidation. This furnished anti-configured monoepoxy alcohols 19 (85% ee) and 20 (94% ee), respectively, or their mirror images (ent-19, 84% ee; en
