Does jefferson retreat from strict construction in his purchase of louisiana? why or why not?

When Thomas Jefferson agreed to buy the territory of Louisiana, he wanted to do it constitutionally, so he wanted to make an amendment to the Constitution first, but the congress did not pay attention to his plans to amend the constitution, and the purchase was made in 1803 but without the legality that it required. For Jefferson's strong values, acquiring territories was a very serious matter, and although it was vital for the USA to purchase Louisiana, as Jefferson expressed it, the Constitution did not give the government powers to buy and maintain territories. But perhaps compromising its principles for the purchase of Louisiana, was something that in 1810 the same Jefferson described as a great achievement and a success, the risk for a great common good to the nation.