Infoscience

Journal article

2-Ethoxyvinyllithiums and diethoxyvinyllithiums: what makes them stable or fragile?

The elusive (E)-2-ethoxyvinyllithium can be readily generated in THF at -75 Deg from (E)-1-bromo-2-ethoxyethylene by halogen/metal exchange and subsequently trapped with electrophiles. Alkylation opens a convenient entry to (E)-configurated enethers. (E)-2-Ethoxyvinyllithium decomps. rapidly at -50 Deg whereas its (Z)-isomer, which lacks the possibility to eliminate LiOEt in a favorable antiperiplanar process, is stable under the same conditions. (E)-1,2-Diethoxyvinyllithium even sustains reflux temps. (.apprx.75 Deg). 2,2-Diethoxyvinyllithium and (Z)-1,2-diethoxyvinyllithium can be conserved at 0 Deg although this time loss of alcoholate can occur in the anti-mode. Obviously it matters whether the energy-rich ethoxyacetylene is formed as the elimination product or simple acetylene, as in the case of (E)-2-ethoxyvinyllithium. [on SciFinder (R)]

    Keywords: Ethers Role: SPN (Synthetic preparation) ; PREP (Preparation) (ene; ethoxyvinyllithiums and diethoxyvinyllithiums for stereoselective prepn. of); Thermal decomposition (of ethoxyvinyllithiums and diethoxyvinyllithiums); Solvent effect (on thermal stabili ; ethoxyvinyllithium prepn stability alkylation; diethoxyvinyllithium prepn stability alkylation; thermal stability ethoxyvinyllithium diethoxyvinyllithium; stereoselective alkylation ethoxyvinyllithium diethoxyvinyllithium; enether stereoselective prepn

    Note:

    CAN 126:199588

    29-2

    Organometallic and Organometalloidal Compounds

    Institut Chimie Organique,Univ. Batiment Chimie,Lausanne-Dorigny,Switz.

    Journal

    0040-4020

    written in English.

    4360-66-1 (2-Bromomethylene-1,3-dioxolane); 26349-94-0 ((E)-1,2-Diethoxyethylene); 28957-42-8 ((Z)-1,2-Diethoxyethylene); 42520-11-6 (2-Bromo-1,1-diethoxyethylene); 98921-98-3 (2-Bromo-1,1-dimethoxyethylene) Role: RCT (Reactant), RACT (Reactant or reagent) (for alkylations via diethoxyvinyllithium); 16339-88-1 ((E)-1-Bromo-2-ethoxyethylene); 23521-49-5 ((Z)-1-Bromo-2-ethoxyethylene) Role: RCT (Reactant), RACT (Reactant or reagent) (for alkylations via ethoxyvinyllithium); 177544-54-6P ((2,2-Diethoxyvinyl)lithium) Role: PRP (Properties), RCT (Reactant), SPN (Synthetic preparation), PREP (Preparation), RACT (Reactant or reagent) (formation, alkylations and thermal stability of); 64724-28-3P ((Z)-(2-Ethoxyvinyl)lithium); 187803-08-3P ((E)-(2-Ethoxyvinyl)lithium); 187803-09-4P ((Z)-(1,2-Diethoxyvinyl)lithium); 187803-10-7P ((E)-(1,2-Diethoxyvinyl)lithium) Role: PRP (Properties), RCT (Reactant), SPN (Synthetic preparation), PREP (Preparation), RACT (Reactant or reagent) (formation, stereoselective alkylations and thermal stability of); 96694-12-1P ((2,2-Diethoxyvinyl)trimethylsilane) Role: SPN (Synthetic preparation), PREP (Preparation) (prepn. from diethoxyvinyllithium); 100-39-0 (Benzyl bromide); 123-72-8 (Butanal) Role: RCT (Reactant), RACT (Reactant or reagent) (reaction with diethoxyvinyllithium); 75-77-4 (Trimethylsilyl chloride) Role: RCT (Reactant), RACT (Reactant or reagent) (reaction with diethoxyvinyllithiums); 187803-06-1P ((Z)-(1,2-Diethoxyvinyl)trimethylsilane); 187803-07-2P ((E)-(1,2-Diethoxyvinyl)trimethylsilane) Role: SPN (Synthetic preparation), PREP (Preparation) (stereoselective prepn. from diethoxyvinyllithium); 14674-80-7P ((E)-3-Ethoxy-2-propenoic acid); 50849-06-4P (Ethyl (E)-1-hexenyl ether); 53715-46-1P ((E)-2-Ethoxyvinyl methyl sulfide); 125555-83-1P ((Z)-(2-Ethoxyvinyl)triethylsilane); 125555-84-2P ((E)-(2-Ethoxyvinyl)triethylsilane); 187802-99-9P; 187803-01-6P; 187803-03-8P; 187803-04-9P; 187803-05-0P ((E)-(2-Ethoxyvinyl)trimethylstannane) Role: SPN (Synthetic preparation), PREP (Preparation) (stereoselective prepn. from ethoxyvinyllithium); 86-84-0 (1-Naphthyl isocyanate); 103-72-0 (Phenyl isothiocyanate); 119-61-9 (Benzophenone); 542-69-8 (Butyl iodide); 624-92-0 (Dimethyl disulfide); 630-19-3 (Pivalaldehyde); 994-30-9 (Chlorotriethylsilane); 1066-45-1 (Trimethylstannyl chloride) Role: RCT (Reactant), RACT (Reactant or reagent) (stereoselective reaction with ethoxyvinyllithium)

    Reference

    Record created on 2006-03-03, modified on 2016-08-08

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