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The organocatalytic asymmetric synthesis of hexahydropyridazines were performed through a unique Michael/amination/cyclization reaction. The organocascade reaction proceeded smoothly between 2-arylidene-1,3-indandiones and aldehydes followed by the addition of azodicarboxylates catalyzed by the privileged organocatalyst α,-α-L-diphenylprolinol trimethylsilyl ether (10 mol%) in the presence of a base additive Et3N (20 mo%) at 0 °C. A series of substituted hexahydropyridazines were obtained in good to high chemical yields (55-78 %) and reasonable to high levels of stereoselectivities (51-93 % ee and 4 : 1 d.r.). [ABSTRACT FROM AUTHOR]

Primary allylic amines serve as suitable allylic electrophiles for the allylation reactions of hypophosphorous acid and H-phosphinic acids. In the presence of tris(dibenzylideneacetone)dipalladium(0) ([Pd2(dba)3], 0.1 mol %) and Xantphos (0.2 mol %), aqueous hypophosphorous acid was allylated by α-unbranched primary allylic amines in a highly regioselective fashion to give structurally diverse allylic H-phosphinic acids in good to excellent yields with exclusive E selectivity. Moreover, increasing the catalyst loading to 1 mol % and adding aqueous phosphoric acid (1.2 equiv.) permitted the allylation of H-phosphinic acids with α-unbranched primary allylic amines to proceed to give disubstituted phosphinic acids in good to excellent yields. [ABSTRACT FROM AUTHOR]

A huge number of indolylglycine derivatives (III) bearing a tetrasubstituted carbon center is efficiently synthesized camphorsulfonic acid catalyzed. Friedel--Crafts reaction of indoles (II) to ketimino esters (I). [ABSTRACT FROM AUTHOR]