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[434935-69-0] C16H12N2O7 (MW 344.28) InChI = 1S/C16H12N2O7/c1-9-5-3-7-11(17(21)22)13(9)15(19)25-16(20)14-10(2)6-4-8-12(14)18(23)24/h3-8H,1-2H3 InChIKey = YEKPNMQQSPHKBP-UHFFFAOYSA-N (reagent used as a coupling promoter to produce esters, lactones, amides, and peptides) Physical Data: mp 178–180 °C. Solubility: sol alcohol, ether, and most organic solvents. Form Supplied in: a white solid; commercially available (TCI, Aldrich). Analysis of Reagent Purity: IR (KBr): 1759, 1820 cm−1; 1H NMR (CDCl3): δ 2.57 (6H, s), 7.53 (2H, dd, J = 7.6, 8.1 Hz), 7.64 (2H, d, J = 7.6 Hz), 8.06 (2H, d, J = 8.1 Hz); 13C NMR (CDCl3) δ 19.1, 121.7, 127.5, 130.5, 136.6, 137.9, 145.1, 160.3; anal calcd for C16H12N2O7: C, 55.82; H, 3.51; N, 8.14; found: C, 55.81; H, 3.39; N, 8.07. Preparative Methods: A solution of 2-methyl-6-nitrobenzoic acid (5.00 g, 27.6 mmol) and thionyl chloride (20.1 mL, 276 mmol) in dichloromethane (50 mL) was stirred for 15 h at room temperature (eq 1). The solvent and thionyl chloride were distilled under reduced pressure at 50 °C and then dichloromethane (40 mL), 2-methyl-6-nitrobenzoic acid (5.00 g, 27.6 mmol), and pyridine (2.40 mL, 30.4 mmol) were successively added at 0 °C. After the reaction mixture had been stirred for 24 h at room temperature, cooled water (100 mL) was added at 0 °C. The mixture was extracted with dichloromethane, and the organic layer was washed with saturated aqueous copper(II) sulfate, saturated aqueous sodium hydrogen carbonate, cold water, and brine, and dried over sodium sulfate. Filtration of the mixture and evaporation of the solvent under reduced pressure produced 8.80 g of the crude 2-methyl-6-nitrobenzoic anhydride (MNBA). The first recrystallization of the crude product from dichloromethane (ca. 90 mL) at 0 °C gave 7.70 g (81%) of pure MNBA as a white solid. (1) Purification: usable after recrystallization. Handling, Storage, and Precautions: stable after recrystallization under argon or nitrogen atmosphere.

[868617-71-4] C8H18O2SeSi (MW 253.27) InChI = 1S/C8H18O2SeSi/c1-7(11-3)8(9-2)10-12(4,5)6/h1-6H3/b8-7- InChIKey = YUIWJVQHUUQPBG-FPLPWBNLSA-N (reagent used as a nucleophile in asymmetric synthesis of organic compounds) Physical Data: bp 31 °C/0.4 mmHg; d 1.178 g cm−3. Solubility: sol alcohol, ether, and most organic solvents. Form Supplied in: a pale yellow oil; commercially unavailable. Analysis of Reagent Purity: IR (neat): 1724, 1655, 1439, 1252, 1221, 1178, 1132, 1097, 901, 843 cm−1; 1H NMR (C6D6): δ 3.30 (s, 3H), 2.13 (s, 3H), 1.87 (s, 3H), 0.30 (s, 9H); 13C NMR (C6D6): δ 152.8, 84.0, 56.0, 17.4, 4.5, 0.2; HR MS: calcd. for C8H18O2SeSi (M+) 254.0241, found 254.0240. Preparative Methods: (1) (eq 1; Step 1) To a suspension of selenium powder (7.0 g, 89 mmol) in THF (177 mL) at 0 °C was added methyllithium in ether (0.98 M, 98 mL, 96 mmol). After the reaction mixture had been stirred for 30 min at 0 °C, methyl 2-bromopropanoate (9.9 mL, 89 mmol) was added to the mixture at −78 °C. The reaction mixture was allowed to warm to room temperature and then saturated aqueous ammonium chloride was added. The mixture was extracted with diethyl ether, and the organic layer was washed with water and brine, dried over sodium sulfate. After filtration of the mixture and evaporation of the solvent, the crude product was purified by distillation to afford methyl 2-methylselenopropanoate (13.3 g, 82%) as a pale yellow oil: bp 82 °C/65 mmHg; IR (neat): 1730 cm−1;1H NMR (CDCl3): δ 3.68 (s, 3H), 3.41 (q, J = 7.3 Hz, 1H), 2.06 (s, 3H), 1.49 (d, J = 7.3 Hz, 3H); 13C NMR (CDCl3): δ 174.0, 52.0, 31.7, 16.9, 3.9; HR MS: calcd. for C5H10O2Se (M+) 181.9846, found 181.9843. (eq 1; Step 2) To a solution of diisopropylamine (1.8 mL, 12.8 mmol) in THF (15 mL) at 0 °C was added n-butyllithium in hexane (1.66 M, 7.8 mL, 12.9 mmol). After the reaction mixture had been stirred for 30 min at 0 °C, a solution of methyl 2-methylselenopropanoate (2.13 g, 11.8 mmol) in THF (10 mL) was added at −78 °C. The reaction mixture was stirred for 1 h at −78 °C and then chlorotrimethylsilane (3.0 mL, 23.7 mmol) was added. After the reaction mixture had been stirred for 1 h at room temperature, it was concentrated by evaporation of the solvent. Petroleum ether was added to the residue, and the suspension was filtered through a short pad of Celite under an argon atmosphere. After evaporation of the solvent, the crude product was purified by distillation to afford a mixture of (Z)- and (E)-1-methoxy-2-methylseleno-1-(trimethylsiloxy)propene (Z/E = 90/10, 2.22 g, 75%). Purification: usable after distillation. Handling, Storage, and Predictions: stable after distillation under argon or nitrogen atmosphere.

[84466-85-30] C11H22N2 (MW 182.31) InChI = 1S/C11H22N2/c1-12-7-5-6-11(12)10-13-8-3-2-4-9-13/h11H,2-10H2,1H3/t11-/m0/s1 InChIKey = VCVPSRADUBPOKJ-NSHDSACASA-N (reagent used as a chiral ligand in asymmetric synthesis of organic compounds) Physical Data: bp 121–123 °C/22 mmHg; d 0.909 g cm−3; ‘α’20D −69 (c 0.5, EtOH). Solubility: soluble in alcohol, diethyl ether, and most organic solvents. Form Supplied in: colorless liquid; commercially available form Tokyo Kasei Kogyo Co., Ltd. (TCI) and Aldrich. Purification: usable without further purification. Handling, Storage, and Precautions: (S)-1-methyl-2-(piperidinomethyl)pyrrolidine and its derivatives can be synthesized from l-proline. Methods for the preparation are described in refs 1b and 2b. Properties of chiral diamines and synthetic intermediates are shown in refs 1b, 2d, and 3b.