“…Starting materials were prepared according to the literature procedures, e.g. (OC) 5 M@C(OMe)R (M ¼ Cr, W; R ¼ Me, Ph) [16], HOCH 2 CH@CHCH 2 NHMe [7] or were used as purchased, without further purification, e.g. HOCH 2 CH@ CHCH 2 OH, SOCl 2 , NH 2 Me, M(CO) 6 (M ¼ Cr, W), MeLi NMR spectroscopy: Bruker ARX 250, DRX 300 and DRX 500 ( 1 H, 13 C); direct single pulse runs, or in the case of the 29 Si and some 13 C NMR spectra by using the refocused INEPT pulse sequence with 1 H decoupling [17], based on 2 J( 29 Si, 1 H) % 7 Hz or n J( 13 C, 1 H) % 3-5 Hz.…”