In situ Crystallization of N(SiMe₃)₃ and As(SiMe₃)₃: Trigonal planar or pyramidal coordination of the central atoms?

Abstract

In situ crystallization technique at low temperature was used to obtain single crystals of the low melting compounds N(SiMe 3 ) 3 1 and As(SiMe 3 ) 3 3. N(SiMe 3 ) 3 has a waxy consistence at room temperature. The solid-state structure of both compounds has been determined by single-crystal X-ray diffraction analysis. N(SiMe 3 ) 3 is distorted and shows nearly a trigonal planar coordination of the central nitrogen atom. In contrast, the heavier homologue As(SiMe 3 ) 3 shows a trigonal pyramidal coordination with Si-As-Si 103.4(6)°-104.9(6)°.

A Convenient One-Pot Synthesis of a Sterically Demanding Aniline from Aryllithium Using Trimethylsilyl Azide, Conversion to β-Diketimines and Synthesis of a β-Diketiminate Magnesium Hydride Complex

“…360 • ) in its molecular structure (Figure 1), c.f. the structure of N(SiMe 3 ) 3 [88], and the metrical features are as expected. A simple aqueous workup of the reaction mixtures afforded crude TripNH 2 6 in good, isolated yields.…”

Theoretical Insights into the Structural Differences between Organic and Inorganic Amines/Ethers

“…Thus, gas-phase electron diffraction (ED) studies on (H 3 Si) 3 N, (Me 3 Si) 3 N, (H 3 Ge) 3 N, and (Me 3 Sn) 3 N species indicate E–N–E angles of about 119.5–120°. Also, measured solid-state structures of (Me 3 Si) 3 N and of (Me 3 Sn) 3 N derivatives reveal planar E 3 N skeletons as well. For organic analogues, computed C–N–C angles in trimethylamine (111.4°) are slightly wider than the tetrahedral values expected, whereas for tris­( tert -butyl)­amine, C–N–C angles (117.5°) are significantly increased presumably due to steric strain gained by adding bulky t -butyl groups to the C 3 N skeleton.…”

In situ Crystallization Technique - an Approach to Circumvent Crystal Structures with high Z′-Crystallization Behavior of (CF3)2C-OH

“…In situ Crystallization and X‐ray Crystallography: Crystals suitable for single‐crystal X‐ray structure analysis were grown from the melt in situ on an X‐ray diffractometer using the method and experimental setup developed by Boese et al This method was already used successfully to obtain single crystals of low melting compounds , , . Small amounts of liquid were introduced into silica capillaries (approximately 2.5 cm long and 0.5 mm in diameter) that were sealed and mounted on the diffractometer.…”