Most experts seem to think that whole brain emulation will not require emulation down to the quantum level, but perhaps at the level of atoms or even molecules, either of which is far more computationally tractable than quantum-level brain emulation. Those who think quantum-level emulation will be required for whole brain emulation are often considered to be cranks.
However, it is worth noting that a few biological processes - including photosynthesis - have recently been found [excellent video lecture] to depend on the particularities of quantum phenomena. This lends no support to Penrose's views on quantum phenomena and the brain, but it may not be so crankish after all to suppose that whole brain emulation may require emulation down to the quantum level.
On photosynthesis, see Fleming's papers on the topic.
Here is the quantum bird navigation paper.
Here is some coverage on Turin's controversial theory of quantum smell.