(gdn: I do not recall the MSM ever reporting that Obama asked Putin to force Assad to get rid of the chemical weapons.)
"...Obama pulled Putin aside, [At the G20 summit in St. Petersburg,] he recalled to me, and told the Russian president “that if he forced Assad to get rid of the chemical weapons, that that would eliminate the need for us taking a military strike.” Within weeks, Kerry, working with his Russian counterpart, Sergey Lavrov, would engineer the removal of most of Syria’s chemical-weapons arsenal—a program whose existence Assad until then had refused to even acknowledge.
http://www.theatlantic.com/magazine/archive/2016/04/the-obama-doctrine/471525/
"...Obama pulled Putin aside, [At the G20 summit in St. Petersburg,] he recalled to me, and told the Russian president “that if he forced Assad to get rid of the chemical weapons, that that would eliminate the need for us taking a military strike.” Within weeks, Kerry, working with his Russian counterpart, Sergey Lavrov, would engineer the removal of most of Syria’s chemical-weapons arsenal—a program whose existence Assad until then had refused to even acknowledge.
http://www.theatlantic.com/magazine/archive/2016/04/the-obama-doctrine/471525/