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D A. Evans Charge Affinity Patterns and the Nitro Functional Group Chem 206 Other Nonalernate Behavior of-NO2 FG Representative examples: O2N 6-2 O CH2R 2 LDA Ph PhCH2Br o CO2Et PhCH2Br o nitronate dianion + N nitronate dianion CO2Et 2LDA Seebach et al. Tetrahedron Lett. 1977. 1161-1164 80% yield O2N--G-C O2N--G-C NO2 As a Leaving Group Seebach et al. Tetrahedron Lett. 1977. 1161-1164 Review. Tamura et al. Synthesis 1991, 423-434 Nitroaliphatic Compounds-ldeal Intermediates in Organic Synthesis Seebach D. etal. Chimia. 1979. 33. 1-18 Representative examples:O2N-C-C Representative examples: O2 N-C(+) CH2Me -O Et PhCH2 Br Q CHzMe SnCl4 2 BuLi NO2 Me3 65%N O O CH R R Nu CH R R + N – O O CH2R + N – O O Ph + N – O O CH2Me 2 BuLi 2 BuLi O2N C C + N – O CH2R – O + N CHR H – O – O H + N – O Et – O + N – O Ph – O O2N C C PhCH2Br Et–I O2N C C + N – O – O H CH2 N CH2 H – O – O + N – O O Ph Et + N – O O CH2Me Bn + N – O O CO2Et + N – O O Ph Me Me SPh NO2 NO2 Ph + N – O – O Ph + N – O – O CO2Et O2N C C SiMe3 SnCl4 O2N C(+) TiCl4 PhCH2Br PhCH2Br Ph Me Me SPh + N – O O Bn Ph + N – O O Bn CO2Et D. A. Evans Chem 206 nitronate dianion Reactivity Patterns (–) (–) – ● ● base base Other Nonalternate Behavior of –NO2 FG Charge Affinity Patterns and the Nitro Functional Group – ● ● base 2(–) Seebach et. al. Tetrahedron Lett. 1977, 1161-1164 Representative examples: – ● ● 51% yield – ● ● 80% yield 40% yield 2(–) Representative examples: (–) (–) 80% yield Seebach et. al. Tetrahedron Lett. 1977, 1161-1164 2 LDA 2 LDA –NO2 As a Leaving Group Representative examples: – + Nu(–) + NO2 – 74% 65% Review: Tamura et. al. Synthesis 1991, 423-434. "Nitroaliphatic Compounds–Ideal Intermediates in Organic Synthesis"' Seebach, D. etal, Chimia, 1979, 33, 1-18 nitronate dianion
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