Is it possible to convert from an IRA to the Roth after 70 1/2 years.

Yes, A conversion may take place but the RMD for the year must be taken first.

But Why would you want to do this? The entire IRA account will be taxed as ordinary income at your marginal tax rate under both federal and state tax laws and you will be left with the remainder of the account to recieve as a distribution. If you plan on using the IRA for retirment needs you should not convert to a Roth IRA.

If you can manage to keep the marginal tax rate low in the year of conversion, such as converting in a year when your income is down (or by doing a staged conversion), you get two possible benefits. You can shut off the dispursement stream and you can leave it in your estate to pass to members of the family that may have a much higher tax rate.

Someone who does not need the income flow, has control over the timing of when they take income, and has heirs that are in high tax brackets would make this more attractive. I am not saying it is easy to craft a significant benefit, but it is possibly worth examining.