3- Amino-4-methoxyacetophenone

The authors reported the chiral separation of proline and thereonine amino acid up to 20 and 6g, respectively, in a single run. Micropreparative resolution of lecucine was presented. The resolution was discussed with respect to the degree of sorbent saturation with copper(II), elution rate, eluent concentration, temperature, and column loading condition [16]. Weinstein [74] reported the micropreparative separation of alkylated amino acids on a Chiral ProCu column. In another article, a preparative chiral resolution of 3-methylene-7-benzylidene-bicyclo[3.3.1]nonane was achieved on 7.5% silver(I)-d-camphor- 10-sulfonate CSP [75]. Later, Shieh et al. [71] used L-proline-loaded silica gel for the chiral resolution of (ft,5 )-phcnylcthanolaminc as the Schiff base of 2-hydroxy-4-methoxyacetophenone. Gris et al. [76] presented the preparative separations of amino acids on Chirosolve L-proline and Chirosolve L-pipecolic acid CSPs. 

The reaction of a-chloro carbonyl compounds with ammonia is not always successful, for example, w-chloro-o-methoxyacetophenone and w-chloro-o,p-dimethoxyacetophenone yield only resinous products (236), but in these cases potassium phthalimide may be used for the ammonation to the a-amino carbonyl compound. This last method was developed by Gabriel (116) and co-workers (187). 

Interaction of the Mannich base from 4-methoxyacetophenone, formaldehyde and dimethylamine over 2 hours in refluxing dimethylformamide with the iminoester hydrochloride of ethyl benzoylacetate, initially converted to the amidine with ammonium acetate, afforded 2-amino-6-(4-methoxyphenyl)pyrid-... 

The above amine (2-amino-6-methoxyacetophenone, 9.9 g) in concentrated hydrochloric acid (260 mL) was diazotised at 0 °C with sodium nitrite (6 g) in water (10 mL). Concentrated hydrochloric acid (250 mL) was added, and after 4 days at room temperature, the solution was rapidly (15 min) evaporated to dryness. The residue in boiling water was treated with excess of hot aqueous sodium acetate, and the precipitate was recrystallized (charcoal) from boiling water. 4-Hydroxy-5-methoxycinnoline (5.80 g) gave pale cream needles from water, mp 275 °C (decomp.). 

Acetaldehyde added to. n-co-amino-p-methoxyacetophenone oxime in ethanol, stirred 1 hr., and heated 10 min. on a water bath -> 6-methyl-3-(p-methoxy-phenyl)-5,6-dihydro-4H-l,2,5-oxadiazine. Y 82%. F. e. s. H. Gnichtel, B. 103, 3442 (1970). 

Preparation by reaction of aluminium chloride with 2-amino-4-methoxyacetophenone in methylene chloride (63%) [2464],... 

Preparation by diazotization of 3-amino-2-hydroxy-6-methoxyacetophenone and replacement of the diazo-nium group by bromine (Sandmeyer reaction) (28%) [2522], (19%) [2523]. 

COCH3 - Preparation by diazotization of 5-amino-2-hydroxy-4-methoxyacetophenone and replacement of diazonium group by chlorine (Sandmeyer reaction) [2530]. 

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