No: Defendants have no reasonable expectation of privacy in conversations they reveal to others. A talkative defendant waives (gives up) the confidentiality of lawyer-client communications by disclosing those statements to someone else. (But if that someone else is a spouse, the statement typically remains at least partially privileged due to a separate evidence rule regarding spousal communications.)
Example: Benny is charged with possession of stolen merchandise. The day after discussing the case with his lawyer, he also talks about it with a neighbor. As long as Benny doesn’t say something to his neighbor like, “Here’s what I told my lawyer yesterday . . .,” the attorney-client communications remain confidential. Of course, Benny’s conversation with the neighbor isn’t confidential—a prosecutor can properly ask the neighbor to testify about what Benny told him.