A Toronto man found guilty of sexually assaulting and strangling a young woman hours after they met is seeking to challenge his murder conviction.

Kalen Schlatter filed a notice of appeal last Wednesday, more than a week after he was found guilty of first-degree murder in the death of 22-year-old Tess Richey.

The verdict means jurors believed beyond a reasonable doubt that Schlatter, 23, sexually assaulted Richey as part of the killing.

First-degree murder carries an automatic sentence of life in prison with no chance of parole for 25 years.

In his notice of appeal, Schlatter alleges the judge who oversaw his trial gave "unbalanced" instructions to jurors before they began deliberations.

He also alleges Ontario Superior Court Justice Michael Dambrot erred in admitting the evidence of two undercover officers who testified they spoke to Schlatter while in neighbouring jail cells after his arrest.