Context : This paper reports a 9-night asteroseismic observation program conducted in January 2007 with the new spectrometer sophie at the OHP 193-cm telescope , on the F5 IV-V target Procyon A .

Aims : This first asteroseismic program with sophie was intended to test the performance of the instrument with a bright but demanding asteroseismic target and was part of a multisite network .

Methods : The sophie spectra have been reduced with the data reduction software provided by OHP .
The Procyon asteroseismic data were then analyzed with statistical tools .
The asymptotic analysis has been conducted considering possible curvature in the échelle diagram analysis .

Results : These observations have proven the efficient performance of sophie used as an asteroseismometer , and succeed in a clear detection of the large spacing .
An échelle diagram based on the 54- \mu Hz spacing shows clear ridges .
Identification of the peaks exhibits large spacings varying from about 52 \mu Hz to 56 \mu Hz .
Outside the frequency range [ 0.9 , 1.0 mHz ] where the identification is confused , the large spacing increases at a rate of about { d } \Delta \nu / { d } n \simeq 0.2 \mu Hz .
This may explain some of the different values of the large spacing obtained by previous observations .

Conclusions :