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Complex of Silylene with Nitrogen: A Combined Matrix‐Spectroscopic and Density Functional Theory Study

“…Simple silylenes, in which the silicon bears a hydrogen atom, can only be detected if pulsed flash pyrolysis (energy transfer not by the hot surface but by collisions with hot Ar atoms or N 2 molecules) is applied 23. 24 Indeed, upon pulsed flash pyrolysis of 9 at 700 °C with Ar as carrier gas and condensation of the products on a spectroscopic window at 10 K, free 1 can be detected. Besides the bands of trimethylsilane, three absorptions at 1992.5, 1972.7, and 1963.9 cm −1 are registered.…”

“…Equipment for the combination of pulsed high‐vacuum pyrolysis with matrix isolation has been described previously 23. 24…”

“…[D 3 ] 9 was prepared by an analogous procedure with LiAlD 4 and obtained as a colorless liquid: 1 H NMR (C 6 D 6 ): δ =0.10 ppm (s, 9 H); 13 C NMR (C 6 D 6 ): δ =−0.4 ppm; 29 Si NMR (C 6 D 6 ): δ =−17.4 (SiMe 3 ), −98.9 ppm (SiD 3 ); IR (gas phase): $\tilde \nu $ =2961.1, 2905.8, 1561.6, 1255.0, 842.4, 748.4, 695.6, 663.3, 617.4 cm −1 ; MS (70 eV): m / e (%)=103 (3) [ M + −D 2 ], 92 (6) [ M + −Me], 73 (100) [SiMe 3 ]; HRMS calcd for C 3 H 9 D 3 Si 2 : 103.038; found: 103.007. For the preparation of [D 2 ] 9 , HBr (25 mL) was condensed with 1,1,1‐trimethyl‐2,2‐diphenyldisilane (2.4 g, 9.3 mmol)24 in a flask (100 mL) at −196 °C. After 7 days at −78 °C, the crude product, which represents mostly highly reactive 1,1‐dibromo‐2,2,2‐trimethylsilane, was directly reduced with LiAlD 4 under standard conditions.…”

cis-3,4-Dichlorocyclobutene as a Versatile Synthon in Organic Synthesis. Rapid Entry into Complex Polycyclic Systems with Remarkably Stereospecific Reactions

“…In contrast, the anti S N 2' attack [6] of the phenylselenyl anion on chlorobutene derivative 9 or 10 or a mixture of the two to furnish directly the E,E-phenylselenodiene 13 (85 % yield) is inferred on the basis of the known propensity of trans-cyclobutene derivatives to open through a conrotatory process at much lower temperatures than their cis counterparts. [7] No phenylselenocyclobutene derivative 12 was detected in this displacement reaction, which suggests both the anti S N 2' mode of reactivity of PhSe À with the chlorocyclobutenes 9 and 10 and the rapid conrotatory opening of the presumed trans-1,2-phenylselenocyclobutene 12 to the E,E-phenylselenodiene 13 at ambient temperature.…”

Carbene Complexes of Nonmetals

“…The linear structure of C 2 Xe is consistent with electron donation from xenon into the vacant 3σ g -orbital that is oriented along the internuclear axis. [156,157] The computed CϪXe bond length of C 2 Xe (approximately 270 pm) [157] is much shorter than the sum of the van der Waals radii (386 pm) but is significantly longer than the experimental CϪXe bond length in (C 6 F 5 ) 2 Xe (235Ϫ239 pm). [158] Scheme 23.…”