Erste funktionalisierte 6,12-Diazatetrakishomocubane

Abstract

Die Photodimerisierung unsymmetrischer 4‐Aryl‐1,4‐dihydropyridine liefert im Unterschied zu den bislang bekannten [2+2]‐Photocycloadditionen symmetrischer 4‐Aryl‐1,4‐dihydropyridine völlig überraschend neuartige 6,12‐Diazatetrakishomocubane 1.

Transition-Metal-Catalyzed Nucleophilic Dearomatization of Electron-Deficient Heteroarenes

“…31 In 2000, the group of Hilgeroth accomplished concise syntheses of cage compounds, 6,12-diazatetrakishomocubanes, in which the key intermediate 4-aryl-1,4-dihydropyridines were acquired through copper-catalyzed nucleophilic dearomatization of N -alkyl-substituted pyridinium salts with Grignard reagents. 32 Based on these preliminary studies, in 2009, the Feringa­ group described a copper-catalyzed enantioselective dearomatization of 4-methoxypyridine with dialkyl­zincs as the nucleophiles through in situ generation of an N -acylpyridinium salt. 33 Using Cu(OTf) 2 as the pre-catalyst and phosphoramidite L12 as the chiral ligand, a number of dialkylzinc nucleophiles smoothly reacted with the N -acylpyridinium salt to give 2-alkyl-substituted dihydropyrido-4-ones in moderate yields and good enantioselectivities after treatment with hydrochloric acid (Scheme 13 ).…”

Using Molecular Symmetry to Form New Drugs: Hydroxymethyl-Substituted 3,9-Diazatetraasteranes as the First Class of Symmetric MDR Modulators

“…[7] The N-Boc derivative 1 c was prepared from 1 b with potassium tertbutoxide. Compounds 1 a and 1 b were obtained by the reaction of nicotinic acid ethyl ester with the methyl and phenyl esters of chloroformic acid followed by regioselective arylation at the 4-position catalyzed by copper(i) iodide (Scheme 1).…”

“…[7] We are currently investigating the causes of the unexpected outcome of this reaction. With the corresponding N-alkylsubstituted monomeric, 1,4-dihydropyridine derivative, tetra-kishomocubane 5 was formed.…”