Abu Omar Saraqeb, who also goes by the name Abu Hajer al-Homsi, was killed during the air raid in a rural part of Aleppo, which rebels say was likely carried out by a USA fighter jet, though the nationality of the jets has not been officially acknowledged.
The source of the air strike has yet to be identified.
Its "emir" Abu Mohammad al-Jolani announced the group's supposed departure from al-Qaeda leadership in July and re-named it as Jabhat Fateh al-Sham.
Along with other leaders, the jihadist figure set up Jaish al Fateh or the army of conquest - a military alliance of Islamist rebel groups that a year ago drove the Syrian army from the northwestern city of Idlib at the height of insurgents' advances.
Russia, the Syrian government and an United States -led coalition all have been carrying out air strikes against militant groups in Syria.
Reuters cited militant sources as saying on Thursday that the commander, known by the nom de guerre Abu Omar Saraqib, was killed in an aerial raid that targeted a meeting of the group's leaders in the village of Kafr Naha.
The embattled city of Aleppo and surrounding districts have viewed some of the fiercest battles in the civil war of Syria.
It's understood they are going to discuss attempts to invent a truce that was national, enhance humanitarian aid deliveries and restart peace talks.
Two rebel sources said on Thursday that Saraqeb had been killed at a location in the countryside near the city of besieged city of Aleppo.
Taking Aleppo would be the biggest victory for Syrian President Bashar al-Assad in five years of fighting, and would demonstrate a dramatic shift of fortunes in his favour since Russian Federation joined the war on his side last year.
Mr Erdogan told Mr Putin that the ceasefire in Aleppo was wanted "when possible", Anadolu news agency reported.