NMR spectra were recorded on a Varian
Inova FT-500 spectrometer and were referenced to the residual deuterated solvent signal. 1 H NMR homodecoupled and NOESY-1D spectra were recorded on the same instrument with the following acquisition parameters: irradiation time 2 s and 256 scans, using standard VARIAN-FT software. 2D NMR spectra were acquired using the same software and processed using an IPC-Sun computer.
Microanalyses were performed with a Perkin-Elmer
2400 CHN analyzer. The specific rotation [a] D 22
was measured at a concentration of 0.1% w/v in toluene or chloroform at 22 ºC on a JASCO P2000
Polarimeter equipped with a sodium lamp operating at 589 nm with a light path length of 10 cm.
The molecular weights (M n ) and the molecular mass distributions (M w /M n ) of polymer samples were measured by Gel Permeation Chromatography (GPC) performed on a Shimadzu LC-20AD GPC equipped with a TSK-GEL G3000Hxl column and an ELSD-LTII light-scattering detector. The GPC column was eluted with THF at 40 ºC at 1 mL/min and was calibrated using eight monodisperse polystyrene standards in the range 580-483 000 Da.
MALDI-ToF MS data were acquired with a Bruker
Autoflex II ToF/ToF spectrometer, using a nitrogen laser source (337 nm, 3 ns) in linear mode with a positive acceleration voltage of 20 kV. 3,3´) .
Otero A., Fernández-Baeza J., Garcés A., Sánchez-Barba L.F., Lara-Sánchez A., Martínez-Ferrer J., Carrión M.P, & Rodríguez A.M. (2017). Highly thermally stable and robust enantiopure zirconium NNN-scorpionates for the controlled ring-opening polymerization of rac-lactide. Dalton transactions (Cambridge, England : 2003), 46(20).
