In maya theres no keyboard toggles for panel types like in max for example mainly because of 3 things.
Workflow is different, you rarely need more than 1 view port for anythingyou can do it easily enough anyway, with the second most often used maya keymayas views are really true cameras and not some virtual bookmark like most other applicationsusually what you do is you tap space, this brings you to your secondary layout, them move your mouse over the view you want to switch to and tap space again. This works well if your secondary layout is 4 way split view (but it probably would be as long as your modeling). Now this sounds tedious but because you allready know what the quadrants are you can just go to the right quadrant and tap 2 times.
So in order to do this on default empty scene:
move your mouse to lower left part of your viewport, and tap space 2 times, back move mouse to upper right and tap 2 times.
But again if you want this just make it but be sure to understand what physical camera actually means versus bookmarks. (the side effect of this si by far one of the coolest fetures ever, you can ling 2 adjoining viewports ths is usefull for example when you for example work with a lowpoly cage in viewport 1 and have highpoly in view port next to it, which refreshes on all idle time)