Well, here I am talking about time again (in my comments to Liza's entry). My forthcoming book is about time, so it is an obsession of mine.
In this case, though, I am thinking very practically. Is it necessary to write a novel chronologically, that is--in the order it will appear when it is finished? This is a question I've discussed lately with students.
My answer for that is no. Write the chapters that come to you. Write them in whatever way works for you. I have written chronologically on some books. On others, I've written chapters like a tourist map of a walking tour; the marked stops help direct the internal journey.
Specifically, on Hiroshima Dreams, I wrote the first two chapters, the middle chapter, and the last chapter at one sitting, and sold the book with that material. Writing the rest of the book was extremely difficult, but no doubt I was helped by my map. I've written beginning and ending chapters first on at least half of my books, then sometimes worked forward and backward as a way to trick myself into reaching that difficult middle territory.
The idea, as always, is to find your process. If you are stalled where you are, it's often helpful to write a later chapter, or maybe even chapters that you might toss. Never restrict yourself, or impose rules on "how things must be done." Within some structures, such as episodic you can shuffle and reorder chapters.
Find your way. Inspiration is precious. Grab it when it comes.