Gas-phase reactions of Si/sup +/ with ammonia and the amines (CH/sub 3/)/sub x/ NH/sub 3-x/ (x = 1-3): possible ion-molecule reaction pathways toward SiH, SiCH, SiNH, SiCH/sub 3/, SiNCH/sub 3/, and H/sub 2/SiNH

Journal Article · Wed Apr 13 00:00:00 EDT 1988 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00216a010· OSTI ID:7148592

Wlodek, S; Bohme, D K

Rate constants and product distributions have been determined for gas-phase reactions of ground-state Si/sup +/(/sup 2/P) ions with ammonia and the amines (CH/sub 3/)/sub x/NH/sub 3-x/ (x = 1-3) at 296 +- 2 K with the selected-ion flow tube technique. All reactions were observed to be fast and can be understood in terms of Si/sup +/ insertion into N-H and C-N bonds to form ions of the type SiNR/sub 1/R/sub 2//sup +/ (r/sub 1/, R/sub 2/ = H, CH/sub 3/) proceeding in competition (in the case of the amines) with hydride ion transfer to form immonium ions of the type CH/sub 2/NR/sub 1/R/sub 2//sup +/ (R/sub 1/, R/sub 2/ = H, CH/sub 3/). C-N bond insertion appears more efficient than N-H bond insertion. The contribution of hydride ion transfer increases with increasing stability of the immonium ion. The latter reaction leads directly to SiH as a neutral product. Other minor reaction channels were seen which lead directly or indirectly to SiCH and SiCH/sub 3/. Rapid secondary proton transfer reactions were observed for SiNH/sub 2//sup +/ and SiNHCH/sub 3//sup +/ to produce gas-phase SiNH and SiNCH/sub 3/ molecules. With methylamine SiNH/sub 2//sup +/ also appears to produce H/sub 2/SiNH/sub 2//sup +/ which may deprotonate to form the simplest silanimine, H/sub 2/SiNH, or aminosilylene, HSiNH/sub 2/. Reactions of this type are of interest in molecular synthesis and here are proposed to contribute to the formation of SiH, SiCH, SiNH, SiCH/sub 3/, and H/sub 2/SiNH or HSiNH/sub 2/ in partially ionized interstellar gas clouds containing silicon, ammonia, and methylamines.

• Research Organization: York Univ., Downsview, Ontario (Canada)
• OSTI ID: 7148592
• Journal Information: J. Am. Chem. Soc.; (United States), Vol. 110:8
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
10 SYNTHETIC FUELS
AMINES
CHEMICAL REACTIONS
AMMONIA
SILICON COMPOUNDS
CATIONS
CHEMICAL BONDS
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
EXPERIMENTAL DATA
GASES
GROUND STATES
CHARGED PARTICLES
DATA
ENERGY LEVELS
FLUIDS
HYDRIDES
HYDROGEN COMPOUNDS
INFORMATION
IONS
KINETICS
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
NUMERICAL DATA
ORGANIC COMPOUNDS
REACTION KINETICS
YIELDS
400201* - Chemical & Physicochemical Properties
090310 - Inorganic Hydrogen Compound Fuels- Properties- (1976-1989)