Über einige Derivate des 2.6‐Lutidins

Abstract

584Aktivitatsstufe 1' chromatogrnphiert wurde. Mit Benzol + Ather und mit Benzol + Chloroform wurdcn Verunreinigungen aus der Saule eluiert; das Dianhydro-adonitoxigenin erschien e n t mit Chloroform. Es wurde aus k h a n 0 1 + Wasser umkristallisiert und schmolz d a m bei 212-214O; Ausb. 28 mg. Es zeigte im' UV ein Maximum der Absorption bei 222 und 339 nip; [a]$: +.541° (~:-=0.2623, in Methanol). C' ,,H,,O, (368.5) -~ ~_ _ _ Ber. C 74.97 H 7.66 Gef. C 74.64 H 7.84 0 x i i n d e s T,i a n h y d r o -a d o n i t o xi g e nin s : 15 mg D i a n h y d r o -a d o n i t o xig e n i n wurden in 0.25 ccm Athano1 mit 7 mg H y d r o x y l a m i n -h y d r o c h l o r i d in iiblicher Weisc umgesctzt.. Es wurden 12 mg unreines Oxim gewonnen, die nach dem Umkristallisieren atis Athanol -+ Wasser hci 249--251° schmolzen. Qualitativ wurde in den Krist,allen N nachgewiesen. C,H,,O,N (383.5) Ber. c' 71.98 H 5.62 Gef. C 71.75 H 8.27 Mon oa n h y d r oad o n i t o x i n a c e t a t : Jeweils 2 mg Ado n i t o x in a c e t a t bzw. 0 it o x i g e n i n a c e t i i t wrirdrn in so vie1 Benzol geliist, daB die lOOfache Menge dca angewandten Aluniiniumoxyds gernde vollkommen durchfeuchtet war. Das GefiiB blieb 1-8 Tage verschlossen stehen. Zur Aufnahme der UV-Absorption wurden dem Ckinisch einigc ccm Methanol zugefiigt, dann wurde das Aluminiumoxyd abgesaugt und nach Auswaschen die Losung i. Vak. eingedanipft. Der Ruckstand kam in Methanol zur Mossung ini Beckman-Apparat DUV.

A Spectrophotometric and Potentiometric Study of Certain Metal Chelates of Pyridine-2,6-dialdoxime.

“…The chelated metal ion showed the expected acid-strengthening effect on dissociation constant of the unchelated oxime groups. This acid-strengthening effect paralleled the chelate stability; a similar effect has been observed before in the acid-dissociation of the 1-hydroxy groups in the metal chelates of 4-(2pyridylazo)-resorcinoi (7), THE ELECTROCHEMICAL Oxidations of the isomers of phenylenediamine and many related compounds have been extensively investigated (5)(6)(7)(8)(11)(12)(13)(14).…”

“…Adams and coworkers (5, 6, 8,12) have determined the final products of electro-oxidation for a number of these compounds and have established in part the reaction mechanisms with the aid of electron paramagnetic resonance (EPR) techniques. Some of the experimental observations reported in the literature (5,12,13) however, have cast considerable doubt on the nature of the reacting species that takes part in the electron transfer reaction at the electrode. For the case of p-phenylenediamine, Adams has postulated that the monoprotonated cation is the reacting species in the pH range 4 to 6 (8).…”

Cationic methylpalladium(II) complexes containing bidentate N–O ligands as catalysts for the copolymerisation of CO and ethylene. Identification and isolation of intermediates from the stepwise insertion reactions, and subsequent detailed mechanistic interpretation ‡

“…All solvents were dried and purified by standard methods and freshly distilled under nitrogen before use. Methyl 6-methylpicolinate was prepared by the method given by Mathes et al 34 The compound [PdMeCl-(COD)] was prepared by the method described by Rülke et al 35 The dimeric complex [PdMe(µ-Cl)PPh 3 ] 2 was prepared according to the method of Ladipo and Anderson, 36 with the exception that CH 2 Cl 2 was used as the solvent instead of benzene. The complex [PdMe(µ-Cl)(PCy C), or to external 85% H 3 PO 4 ( 31 P).…”