Pyridines 2-formyl

Milosevic, M., Andjelkovic, D., and Binenfeld, Z. Effets de divers oximes, derives de chlorures de 1-phenyle, 1-benzyle et 1-phenacyle pyridine et les analogues de 4-formyle pyridin dans 1 intoxication au paraoxon. Med. Exp. 10 73-78, 1964. 

Mit 2-Formyl-pyridin entstehen 2-Amino-4-(2-pyridyl)-5-hydroxy-1,3-oxazole7,8, die ebenfalls zu Ami-nosauren verseifbar sind1. 3- und 4-Formyl-pyridine ergeben nur die entsprechenden 2,4-Dioxo-5-[3-(bzw.4)-pyridyl]-imidazolidine. 

Electrolytic reductions of 2- or 4-pyridylmethanol,58 4-formyl-pyridine,48 and 4-pyridinecarboxylic acid59,60 afford mixtures of the corresponding methylpyridine, methyl-3-piperideine, and methyl-piperidine. 

Of the pyridine aldehydes, only Schiff s bases (192) from 3-formyl-pyridine and anilines such as p-chloroaniline, which with the stilbazole 190 forms l,4-bis[/3-(3-pyridyl)vinyl]benzene (193), have been found to undergo the Anil Synthesis.34... 

A clean vessel was charged with water (20 gal), sodium hydrogen phosphate (25 kg, 183.5 mol), 5-(2-formyl-pyridin-2-yloxy)-benz[l,2,5]oxadiazole (15 kg, 62 mol), and Zert-butyl alcohol (99 gal). The mixture was stirred for 1 h, and then a solution of sodium chlorite (34 kg, 379 mol) in water (40 gal) was added at a rate to keep the internal temperature < 35 °C. The reaction was quenched with a solution of sodium bisulfite (90 kg) in water (99 gal) at a rate to keep the temperature < 25 °C. The tert-butyl alcohol was stripped at slightly below atmospheric temperature (to control the bisulfite fumes released) until the head temperature was 80 °C. After cooling to 20 °C, the solids were stirred for 5.5 h, filtered, and washed with water (10 gal). The wet cake was reslurried in water (30 gal) for 1 h at 80 °C. After cooling to 20-25 °C, the solids were slurried for 2 h, filtered, and washed with water (5 gal). The solids were dried in a vacuum oven at 45-55 °C until the KF was < 0.5%, yielding 14.3 kg (89%) of the desired product. 

Ebenso wie 2-(Alkoxy-methyl)-pyridin-1-oxide (s. S. 302) lagern sich auch die entspre-chenden Sulfane7 8 in siedendem Essigsaureanhydrid durch intramolekulare Redoxreak-tion uber Enthiolether-Zwischenstufen in isolierbare 0,S-Aceta e (84%) um, deren Hydrolyse mit 20% waBr. Salzsaure 2-Formyl-pyridine (86%) liefert7 ... 

Formyl-pyridine sind aus 2-Chlormethyl- bzw. 2-Brommethyl-pyridin-N-oxiden durch Umsetzen mit Acetanhydrid und anschlieBende Hydrolyse zu erhalten157,138 (s. S. 372) ... 

R = 2,4-CI2-C6H3 2,4-Dichlor-benzaldehyd 47% R = Pyridyl 2-Formyl-pyridin 47%... 

N CO—OC2H5 CO-OC2H5 Toluol/ [(H3C)2CH-CH2]2AIH 2 -70 4-Ethoxycarbonyl-2-formyl- pyridin 42 165... 

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