The present invention provides, in part, compounds of Formula I: and pharmaceutically acceptable salts thereof; processes for the preparation of; intermediates used in the preparation of; and compositions containing such compounds or salts, and their uses for treating D1-mediated (or D1-associated) disorders including, e.g., schizophrenia (e.g., its cognitive and negative symptoms), cognitive impairment (e.g., cognitive impairment associated with schizophrenia, AD, PD, or pharmacotherapy therapy), age-related cognitive decline, dementia, and Parkinson's disease.