If 45 minutes is not very far for him to travel, why is it far for you? That's the question the Judge will ask you when you go before him/her to ask for permission to leave the state. And you should ask for such permission before leaving or you may be brought back and then you'll have to explain why you left in the first place without seeking permission from the Court.
Its always best to try to work out something with your husband first or go into court and ask for permission so your husband doesn't claim you abandoned him and abscounded with the child.
It would be best to first get an attorney to represent you so you don't have to face these hurdles without assistance.
You should attempt to obtain your spouse's consent to the move. If there is no consent, the move would undoubtedly become an issue in the divorce that could affect some of the economic decisions.
You should consult with a local attorney to discuss how Massachusetts courts would likely decide the issue.
Not that I disagree with the other info provided, but have you considered asking your spouse if he would consider mediation? Mediation can be a very effective way to address parenting issues such as yours, and can lead to a workable solution that you both can live with. Of course, you will want to consider what is in the best interest of your son, which is the main principle used by the courts to decide child-related issues. Frequently, the thinking is that a child's interests are best served by having two involved, loving parents. Of course, this could be a possibility if under an hour away.
Finally, keep in mind that mediation is oftentimes a less expensive option than a litigated case, and the less adversarial process can encourage better post-divorce parenting! Good luck with your case.
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