International scientific collaboration for a network mission to Mars

For the past 15 years here has been a strong consensus within the international scientific community in favor of sending a network of geophysical observatories to Mars. These landers would probe the interior of the planet through seismic monitoring, magnetic sounding, and measurements of its rotational dynamics. They would study the global circulation and regional dynamics of the atmosphere and through imaging would reveal the geology of a host of new places on the surface. The enthusiasm for this endeavor has been manifested in a number of mission studies, includiung MESUR Network, MarsNet and InterMarsNet. At the beginning of the 21st century the goal was close to being realized with the NetLander mission, which was sponsored by a broad consortium of nations in Europa and America. Unfortunately, budget difficulties and programmatic conflicts at CNES and NASA resulted in recent cancellation. However the scientific priorities for understanding the origin, evolution, environment and habitat of Mars remain, and a geophysical network is clearly required to make the measurements necessary to address these questions. A large group of scientists remain committed to goal of deploying an international Geoscience Observatory on Mars, whose data would be available to the world science community, and we welcome the participation of all who share this aim. To this end, we are exploring all international options, including ESA's Aurora program, the Scout programm of NASA's Mars Exploration Program, and NASA's new exploration initiatives

Synthesis Of Trialkylamines With Extreme Steric Hindrance And Their Decay By A Hofmann-Like Elimination Reaction

A number of amines with three bulky alkyl groups at the nitrogen, which surpass the steric crowding of triisopropylamine considerably, were prepared by using different synthetic methods. It turned out that treatment of N-chlorodialkylamines with organometallic compounds, for example, Grignard reagents, in the presence of a major excess of tetramethylenediamine offered the most effective access to the target compounds. The limits of this method were also tested. The trialkylamines underwent a dealkylation reaction, depending on the degree of steric stress, even at ambient temperature. Because olefins were formed in this transformation, it showed some similarity with the Hofmann elimination. However, the thermal decay of sterically overcrowded tertiary amines was not promoted by bases. Instead, this reaction was strongly accelerated by protic conditions and even by trace amounts of water. Reaction mechanisms, which were analyzed with the help of quantum chemical calculations, are suggested to explain the experimental results