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In a 500-mL 3-necked round bottom flask equipped with a stirrer, thermometer, and 15°-20° C. water bath was placed 40 g (0.264 moles, 1.0 equiv.) of 4-ethylnitrobenzene, 230 mL of methanol, 30 mL of water, 30.8 g (0.2904 moles, 1.1 equiv.) of benzaldehyde, and 36.6 g (0.561 moles, 4.25 equiv.) of zinc powder. The reaction mixture, with vigorous stirring, was cooled to 15°-20° C. and the dropwise addition of 79.2 (1.32 moles, 5.0 equiv.) of acetic acid was begun. The reaction mixture was allowed to exotherm to 34°-36° C., and the temperature was held there throughout the 30 minute addition period. When the addition was complete, the reaction temperature was held at 35° C. with a steam pot for 1 hour. The reaction flask was placed under full aspirator vacuum and the reaction mixture was stripped to about 1/3 volume. Xylene (100 mL) was added to the reaction mixture to azeotrope water from the reaction mixture. This azeotrope step was repeated 2 more times with fresh xylene. The zinc acetate salts were filtered off. The xylene/product liquors were stripped to an oil under aspirator vacuum. Dichloromethane (250 mL) was added to the product oil and cooled to 0° C. Via an addition funnel, 49.6 g (0.273 moles, 1.033 equiv.) of trichloroacetyl chloride was added maintaining the reaction temperature below 20° C. The resulting dark solution was warmed to 25° C. and held here for 15 minutes to form a compound of this invention having Formula (I). Acetic acid (44 mL) was added in one portion, followed by 27 g (0.32 moles, 1 equiv.) of concentrated hydrochloric acid. The reaction mixture was heated, and the low boiling liquid (lower than 50° C.) was distilled off. When the pot temperature reached 78°-80° C. and no more volatile liquids distilled, the reaction was allowed to reflux for 3 hours (at 78°-85° C.). The reaction was cooled to 50° C. and 600 mL of ethyl acetate was added in one portion. The dark solution was stirred and cooled to 15°-20° C. The 2-amino-5-ethylphenol hydrochloride came out of solution slowly. The mixture was stirred at 15°-20° C. for 30 minutes then collected and washed with ethyl acetate and heptane. The fluffy yellow-orange crystals were dried in a warm air oven overnight. The 24.4 g yield of 15 was 53.2% of the theoretical: MP 218° C.±2° C.; HPLC (area %) 78.0%; IR (KBr)16 (OH) 3.0μ and 7.0μ, (--NH2.HCl) 3.9μ and 5.25μ; NMR (DMSO-D6, Me4Si) δ1.1 (t,3H), 2.5 (q,2H), 6.65 (d, 1H), 6.9 (S, 1H), 7.3 (T, 2H), 10 (S, 2H), 10.7 (S, 1H); TLC (1 BuOAc, 2 PhCH3, 4 CHCl3), silica-gel-coated plates, viewed under short-wave UV light, major spot for 15, Rf =0.18.

1. customIn a 500-mL 3-necked round bottom flask equipped with a stirrer
2. temperatureThe reaction mixture, with vigorous stirring, was cooled to 15°-20° C.
3. customto exotherm to 34°-36° C.
4. additionthe temperature was held there throughout the 30 minute addition period
5. additionWhen the addition
6. filtrationThe zinc acetate salts were filtered off
7. additionDichloromethane (250 mL) was added to the product oil
8. temperaturemaintaining the reaction temperature below 20° C
9. temperatureThe resulting dark solution was warmed to 25° C.
10. waitheld here for 15 minutes
11. customto form a compound of this invention
12. temperatureThe reaction mixture was heated
13. distillationthe low boiling liquid (lower than 50° C.) was distilled off
14. customreached 78°-80° C.
15. distillationno more volatile liquids distilled
16. temperatureto reflux for 3 hours (at 78°-85° C.)
17. temperatureThe reaction was cooled to 50° C.
18. addition600 mL of ethyl acetate was added in one portion
19. temperaturecooled to 15°-20° C
20. stirringThe mixture was stirred at 15°-20° C. for 30 minutes
21. customthen collected
22. washwashed with ethyl acetate and heptane
23. customThe fluffy yellow-orange crystals were dried in a warm air oven overnight