Darstellung und Eigenschaften von und Reaktionen mit metallhaltigen Heterocyclen, XI¹⁾ Darstellung und Eigenschaften von Ethandiyl‐, Propandiyl‐, Pentandiyl‐ und Decandiyl‐bis(trifluormethansulfonat)

Abstract

Vor kurzem berichteten wir ilber einen neuen Zugang zu Metallacycloalkanen aus Metallkomplexen mit zwei nucleophilen Zenfren und a,wdisubstituierten Kohlenwasserstoffen I -5 ) . Von besonderer Bedeutung filr den Ablauf der Reakfionen ist die Natur der Abgangsgruppe in den Alkanen. Sie muD so beschaffen sein. daD die a,wstgndigen C-Aiome eine moglichst hohe 5( 2 ) Chem. Ber. 114(1981)

Synthesis of a Series of Structurally Diverse MB327 Derivatives and Their Affinity Characterization at the Nicotinic Acetylcholine Receptor

“…The following compounds were prepared according to published methods:p ropane-1,3-diyl bis(trifluoromethanesulfonate) (21), [44,45] 2-tert-butylpyridine (17), [27] 2-(pyridin-3-yl)propan-2-ol (9), [33] rac-nicotine (rac-26), [28] 1-(tert-butyl)-1H-imidazole (41) [29] and the 4-tertbutyl-substituted pyridine derivatives 4-(tert-butyl)-3-methylpyridine (33), 4-(tert-butyl)-3-methoxypyridine (31), 4-(tert-butyl)-3chloropyridine (28), 3-bromo-4-(tert-butyl)pyridine (29), 4-(tert-butyl)pyridine-3-carbonitrile (30), ethyl 4-(tert-butyl)pyridine-3-carboxylate (36), 4-(tert-butyl)-3-fluoropyridin-1-ium chloride (27), 4-(tertbutyl)-3-phenylpyridine (34), 4-(tert-butyl)-N,N-dimethylpyridine-3carboxamide (32), and 4-(tert-butyl)-3-ethynylpyridine (35). [30] Generalprocedures Synthesis of symmetric bispyridinium compounds by N-alkylation with 21 (GP1): 21 (1.0 equiv) was carefully added to asolution of the corresponding pyridine derivative (2.5 equiv) in CH 2 Cl 2 (0.8 mL mmol À1 )o rt ot he neat pyridine derivative (2.5 equiv) at room temperature.…”

“…The following compounds were prepared according to published methods:p ropane-1,3-diyl bis(trifluoromethanesulfonate) (21), [44,45] 2-tert-butylpyridine (17), [27] 2-(pyridin-3-yl)propan-2-ol (9), [33] rac-nicotine (rac-26), [28] 1-(tert-butyl)-1H-imidazole (41) [29] (35). [30] Generalprocedures Synthesis of symmetric bispyridinium compounds by N-alkylation with 21 (GP1): 21 (1.0 equiv) was carefully added to asolution of the corresponding pyridine derivative (2.5 equiv) in CH 2 Cl 2 (0.8 mL mmol À1 )o rt ot he neat pyridine derivative (2.5 equiv) at room temperature.…”

Unusually Facile Syntheses of Diquat (6,7-Dihydrodipyrido[1,2-a:2′,1′-c]pyrazinediium) and Related Cations

“…We also report here an alternative method for the preparation of diquats under mild conditions by using 1,2-bis[(trifluoromethylsulfonyl)oxy]ethane [1,2-bis(triflyloxy)ethane, DTE] 11 as the diquaternising agent. It is well established that trifluoromethanesulfonate (triflate) has a leaving group ability several orders of magnitude higher than that of bromide, and we have found that diquaternisations with DTE proceed at room temperature in various solvents.…”

“…The compounds DTE, 11 4-hydroxymethyl-4¢-methyl-2,2¢-bipyridyl, and 4-bromomethyl-4¢-methyl-2,2¢-bipyridyl 13 were prepared according to published procedures. All other reagents were obtained commercially and used as supplied.…”

Darstellung und Eigenschaften von Reaktionen mit metallhaltigen Heterocyclen, VIII. Schwefeldioxid‐ und Kohlenmonoxid‐Einschiebungsreaktionen in die Metall‐Kohlenstoff‐σ‐Bindung von Metallacycloalkanen

“…Aktiviert man jedoch metallkoordiniertes Kohlenoxid in 1 b' mit einer Lewis-Saure wie AlBr,,'), Darstellung und Eigenschaften von und Reaktionen rnit metallhaltigen Heterocyclen, VIII so erhalt man in Toluol das farblose, extrem feuchtigkeits-und sauerstoffempfindliche Addukt 3b', welches drucklos bei 20°C CO aufnimmt und bei der anschliefienden Hydrolyse in das ringerweiterte, farblose, thermisch labile Insertionsprodukt 4b' ubergeht [Gl. (3)]. Bei dieser Umsetzung handelt es sich um die erste CO-Einschiebung in eine Re -C-o-Bindung rnit sp3-hybridisiertem Kohlenstoff.…”