“…Yield 3.89 g (78%), dark-yellow crystals. 1 Н NMR spectrum (CDCl 3 ), δ, ppm: 0.97 d (12H CH 3 , J 6.9 Hz), 1.24 d (12H, CH 3 , J 6.9 Hz), 3.04 heptet (4H, CH, J 6.8 Hz), 6 1 Н, 13 С NMR spectra were registered on a spectrometer Bruker Avance 400 DPX at operating frequencies 400 and 100 MHz respectively. Chemical shifts are reported with respect to TMS signal.…”