, CDCl 3 ) ? = 157.12 (C-1), 146.53 (C-2), 136.65 (C-3), 130.33 (C-4), 129.52 (C-2), 0.32 (s, 18H, CH 3 ) ppm. 13 C{ 1 H} NMR (126 MHz, pp.117-73
, Mp (DSC; Onset): 102.37 ? C 4.2.3. 2,2 -Bis(trimethylsilyl)azobenzene (6) In an inert tube 2,2 -bis(trimethylstannyl)azobenzene (4) (80.0 mg, 0.16 mmol) was dissolved under Schlenk conditions in THF (5.00 mL) and cooled to ?78 ? C. MeLi (1.88 M in THF, 0.25 mL, 0.47 mmol) was added within 5 min and after 1 h at this temperature, trimethylsilyl chloride (9) (200 µL, 171 mg, 1.57 mmol) was added to the black reaction mixture in one portion. The reaction mixture was warmed to 25 ? C over 14 h and the solvent was removed under reduced pressure. The brown solid, dissolved in DCM (3.00 mL), was purified by a short plug of silica (eluent: n-pentane). The first orange fraction was filtered through a PTFE filter (0.45 µm). From the filtrate, the solvent was removed to obtain an orange solid
, C-3), 130.14/130.11 (C-4 and C-5), 114.68 (C-6), CDCl 3 ): ? = 4.04 ppm. IR (ATR): ? = 3059 (w), 2946 (w), 2987 (w), 2853 (w), 1968 (w), 1937 (w), 1859 (w), 1737 (w), 1581 (w), 1561 (w), 1465 (w), 1424 (w); 1296 (w), 1241 (m), 1119 (m), 1075 (w), 831 (s), 778 (s), 747 (m), vol.720, p.16290
, A schlenk tube was filled with 2,2 -bis(trimethylstannyl)azobenzene (4) (80.0 mg, 0.16 mmol) in THF (5.00 mL) and cooled to ?78 ? C. Then, MeLi (1.88 M in THF, 0.25 mL, 0.47 mmol) was added within 5 min and after 1 h at this temperature, trimethylgermanium chloride (14) (200 µL, 171 mg, 1.57 mmol) was added to the dark reaction mixture in one portion. The reaction mixture was warmed to 25 ? C over 14 h and the solvent was removed under reduced pressure. The brown solid, CDCl, vol.3, issue.7
, C-4), 129.52 (C-2), 2962 (w), 2905 (w), 1563 (w), 1463 (w), 1432 (w), 1407 (w), 1295 (w), 1234 (m), 1114 (m), 1064 (w), 953 (w), 818 (m), vol.130, p.751
, R f (n-pentane): 0.78. Mp (DSC; Onset): 82.85 ? C 4.2.5. 2,2 -Di(tert-butyl)azobenzene (10) Adapted with changes from Takahashi et al. [26] 2-tert-butylaniline (15) (5.00 g, 33.5 mmol) was dissolved in toluene (800 mL), HRMS (APCI): m/z calcd
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