“…Tetralone 1 was reacted with N -propylamine under reductive amination reaction conditions to give 2 , which was resolved by chiral 4-(2-chlorophenyl)-2-hydroxy-5,5-dimethyl-1,3,2-dioxaphosphorinane 2-oxide, prepared according to the literature. 22 Then, N-alkylation of (±)- 2 , (+)- 2 , and (−)- 2 with ethylbromoacetate in acetonitrile in the presence of K 2 CO 3 was achieved to produce compounds (±)- 3 , (+)- 3 , and (−)- 3 in quantitative yield. Nitration of these compounds was achieved by using fuming HNO 3 to yield 7-nitro derivative (±)- 4 , (+)- 4 , (−)- 4 exclusively.…”