Solution
Outlook._NameSpace olNs;
Outlook.MAPIFolder oSents;
Outlook.Items oItems;
olNs = olApp.GetNamespace("MAPI");
oSents = olNs.GetDefaultFolder(Outlook.OlDefaultFolders.olFolderSentMail);
oItems = oSents.Items;
DateTime dateTime = Convert.ToDateTime("11/25/2013");
oItems = oSents.Items.Restrict("[ReceivedTime]='" + dateTime);