Bis‐Dichlorosilyl Functionalized C 4 ‐Cumulene With Unique Bonding Scenario

ABSTRACT This work reports the preparation and computational investigation of a bis‐dichlorosilyl functionalized C 4 ‐cumulene ( 2 ), which was synthesized by employing Amidinato‐chlorosilylene, L(Cl)Si: (L = PhC(N t Bu) 2 ). Compound 2 was characterized by single‐crystal X‐ray diffraction, mass spectrometry, and NMR spectroscopy. The stability, distribution of spin densities, and the nature of Si‐C bonds of 2 were studied by employing natural bond orbital (NBO) analysis, atoms in molecules (AIM), and energy decomposition analysis‐natural orbital for chemical valence (EDA‐NOCV). The EDA‐NOCV analysis showed that compound 2 possesses electron‐sharing covalent sigma and dative covalent sigma bonds (Si↔C and C→Si) between the Ph 2 C 4 fragment in the anionic doublet state and silyl‐amidine groups in the cationic doublet state. This may be due to the electron‐deficient nature of olefin and electron‐rich N‐donating functional groups on silicon atoms. Compound 2 displays unprecedented chemical bonding in this class of compounds as predicted by EDA‐NOCV calculations. We have also compared the bonding situation of compound 2 with a previously reported compound 3 .