Communication

A Gas-Phase Model for the Pt⁺-Catalyzed Coupling of Methane and Ammonia

Massimiliano Aschi, Mark Brönstrup, Martin Diefenbach, Jeremy N. Harvey, Detlef Schröder^*, Helmut Schwarz^*

Institut für Organische Chemie der Technischen Universität, Strasse des 17. Juni 135, D-10623 Berlin (Germany), Fax: (+49) 30-314-21102

email: Detlef Schröder (schw0531@www.chem.tu-berlin.de)

Keywords

Ammonia; Gas-phase chemistry; Hydrogen cyanide; Methane; Platinum

FULL TEXT

Abstract

What exactly are the elementary steps in the Pt-catalyzed coupling of methane and ammonia (Degussa process) shown on the right? Mass spectrometry and ab initio theory have been used to probe the mechanistic details of this technically important synthesis of hydrogen cyanide.

Received: 3 November 1997. -3 kcal mol^-1. The PA of C₂H₅ONO₂ is computed to be 177 ± 2 kcal mol^-1 at 298 K, irrespective of whether protonation occurs at the ethereal O or at the NO₂ group, in excellent agreement with the experimental value. The results are discussed in connection with the general problem concerning the preferred protonation site and the PA trend along the RONO₂ homologous series. It is shown that entirely different factors control the local PA of the RO and the NO₂ groups.