2- Alkyl-6-methyl pyridine

The direct conversion of an a-amino acid into the corresponding a-acetylamino-alkyl methyl ketone, via oxazoline (azalactone) intermediates. The reaction proceeds in the presence of acetic anhydride and a base such as pyridine with the evolution of CO2. 

Aromatic N-containing heterocycles (pyridine, imidazole etc.,) and their alkyl derivatives represent an important group of products and they have received considerable attention because of their various applications. For instance, methyl pyridines (picolines) and dimethyl pyridines (lutidines) are a class of industrially valuable compounds for the production of dyes and fine chemicals [108]. Sreekumar et al [109] reported pyridine methylation to 3-picolines over Zni xCoxFe204 spinel systems at reaction temperature between 325 and 425°C. The... 

Table 5 Relative Rates of Alkylation of Pyridine Compared with Quinoline and 2-Methyl-...

Activation of alkyl substituents is illustrated by the synthesis of the isomeric pentylpyridines (Expt 8.33) and ethyl 2-pyridylacetate (Expt 8.32, cognate preparation). Thus removal of a proton from the 2-methyl group of 2-methyl-pyridine (2-picoline) with the aid of base (e.g. sodamide) gives a mesomerically... 

A European patent granted to Quest International Services BV involves use of pyridine derivatives as fragrance materials. 2-Alkyl-substituted pyridines are specifically mentioned, including all possible stereoisomers of 2-(2,4-dimethylcyclohexyl)pyridine 46, which is made from 2-vinylpyridine and 2-methyl-l,3-pentadiene via the Diels-Alder reaction <2006EP01562904>. 

Schug and co-workers found a good correlation between the calculated activation energy [A -(calc)] and the logarithms of the methylation rate constants for 37 alkyl-substituted pyridines and 6 hetero-substituted pyridines (83JOC4892), including 30 ortho derivatives. 

Some Aspects of the Direct Alkylation of Pyridine and Methyl Pyridines... 

Ober Rhodium/Aluminiumoxid werden 3-Hydroxy-2-(dimethylamino-methyl)-pyri-din sowie 3-Hydroxy-2,6-bis-[dialkylamino-methyl]-pyridine in Salzsaure bei 307140 bzw. 160 bar mit sehr guten Ausbeuten zu den entsprechenden Piperidinen hydriert1 2. 3-Hydroxy-6-propyl-pyridin liefert mit Platin(IV)-oxid in Essigsaure (2073 bar) 96% d.Th. 3-Hydroxy-6-propyl-piperidin3. Analog werden 3-Hydroxy-l-alkyl-pyridinium-bromide iiber Raney-Nickel in Wasser (1507130 bar) hydriert4. 

R -CH2 X r C=CH-N(CH3)2 X 1,3-Dicarbonyl-Verbindungcn, Nitrile, Ketone, Ester, Alkyl-nitro-bcnzole, Methyl-pyridine, -pyrimidine, Fluoren, Xanthen reagieren in hohen Ausbeuten... 

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