Using the listdlg and msgbox functions (because I like them), this works:
x= ['08-11-2014 07:45'
'10-12-2014 08:00'
'09-12-2014 08:15'
'09-12-2014 08:30'];
Y= [2
5
6
7];
[dateidx,v] = listdlg('PromptString','Select a date', 'SelectionMode', 'Single', 'ListString',x);
msgbox(sprintf('The value corresponding to %s is %0.2f',x(dateidx,:),Y(dateidx)), 'Result');
