The invention provides certain (phenyl)-(pyrazol)-3,4-dihydroisoquinolin-2(1H)-yl)ethan-1-one compounds of formula I as D1 positive allosteric modulators (PAMs), and pharmaceutical compositions thereof. The invention further provides methods of using a compound of formula I, or a pharmaceutically acceptable salt thereof, to treat certain symptoms of Parkinson's disease, schizophrenia, ADHD or Alzheimer's disease.; 展开▼