Organocatalytic inter- and intramolecular [4+2] and [3+3] cycloadditions of α,β-unsaturatedaldehydes to give polysubstituted aromatic aldehydes are described. High periselectivity for the cycloadditions, with catalyst effects exerted by l-proline and pyrrolidine–HOAc, as well as cocatalyst, additive effects, has been observed.
Use of bis(3,4-dialkylbenzylidene) sorbitol acetals and of compositions containing it
申请人:MILLIKEN RESEARCH CORPORATION
公开号:EP0421634A2
公开(公告)日:1991-04-10
Bis(3,4-dialkylbenzylidene) sorbitol acetals are provided for the formula:
in which R₁ and R₂ are independently selected from lower alkyl groups containing 1-4 carbon atoms, or together form a carbocyclic ring containing up to 5 carbon atoms.
Bis(3,4-dialkylbenzylidene) sorbitol acetals and compositions containing same
申请人:MILLIKEN RESEARCH CORPORATION
公开号:EP0647643A1
公开(公告)日:1995-04-12
Bis(3,4-dialkylbenzylidene) sorbitol acetals are provided of the formula:
in which R₁ and R₂ are independently selected from lower alkyl groups containing 1-4 carbon atoms, or together form a carbocyclic ring containing up to 5 carbon atoms. They are useful as plastic additives.