Described is a Pd/C‐catalyzed dehydrogenative [3+2] cycloaddition for the synthesis of benzo‐fused tropanes. The reaction proceeds through a sequential Pd/C‐catalyzed dehydrogenative formation of azomethineylides from amines and 1,3‐dipolarcycloaddition.
Intermediates for the preparation of microficidal pyrroline derivatives
申请人:Ciba-Geigy Corporation
公开号:US04778901A1
公开(公告)日:1988-10-18
Intermediates for the production of microbicidal pyrrolines of the formula ##STR1## in which R is halogen, C.sub.1 -C.sub.6 -alkyl or C.sub.1 14 C.sub.6 -haloalkyl, and n is 0, 1 or 2, and a method of converting the pyrrolines to phytofungicidal pyrroles by oxidation with bromine or oxygen. Catalysts are provided for the oxidation with oxygen.
Method of and bait compositions for controlling mollusks
申请人:AMERICAN CYANAMID COMPANY
公开号:EP0312723A2
公开(公告)日:1989-04-26
This invention relates to methods of controlling mollusks with arylpyrrole compounds and to bait compositions containing a molluscicidally effective amount of an arylpyrrole compound.
In search of diamine analogs of the α,α-diphenyl prolinol privileged chiral organocatalyst. Synthesis of diamine derivatives of α,α-diphenyl-(S)-prolinol and their application as organocatalysts in the asymmetric Michael and Mannich reactions
This paper describes improved reaction conditions for the substitution of the hydroxyl group in (S)-diphenyl(pyrrolidin-2-yl)methanol by the azide group, which was then reduced to the diamine derivative. We examined two protecting groups (N-Bn and N-Boc) on the pyrrolidine nitrogen in order to functionalize the primary amino group into various amide, alkylated amine, sulfonamide, thiourea and triazole derivatives. Notably, carefully controlled conditions were required to generate the desired derivatives from the sterically hindered benzhydrylamine moiety. Unexpectedly, upon removal of the N-protecting group in derivatives containing electrophilic polar double bonds (C=S, C=O) cyclization took place, affording products such as amidines. The target compounds were evaluated as bifunctional organocatalysts in the asymmetric Michael and Mannich addition reactions. (S)-2-(Azidodiphenylmethyl) pyrrolidine (S)-7 was identified as the most efficient organocatalyst among the various diamine derivatives of alpha,alpha-diphenyl-(S)-prolinol prepared in this work. (C) 2015 Elsevier Ltd. All rights reserved.
DABCO-mediated aza-Michael addition of 4-aryl-1H-1,2,3-triazoles to cycloalkenones. Regioselective synthesis of disubstituted 1,2,3-triazoles
Aza-Michael addition of 4-aryl-1H-1,2,3-triazoles to 2-cycloalken-1-ones has been studied in the presence of DABCO as organic base. The reactions were carried out in acetonitrile at room temperature to provide 2,4-disubstituted 2H-1,2,3-triazoles as major adducts and 1,4-disubstituted 1H-1,2,3-triazoles as minor adducts. Though the reaction times are longer (4-8 days), the two regioisomers were separated by using column chromatography and the adducts were obtained in very good to excellent combined chemical yields. The electron-rich and electron-poor substituents on aryl moiety of 4-aryl-triazoles could tolerate the reaction conditions to afford the title adducts. (C) 2016 Elsevier Ltd. All rights reserved.