The First Vatican Council established that the pope is infallible when,
by virtue of his supreme Apostolic authority, he defines a doctrine regarding faith or morals [de fide vel moribus] to be held by the universal Church
(source: "What is meant by “faith and morals” with regards to papal infallibility?")
Now, Pope Pius XI, discussing the abuse of matrimony in Casti Connubii, 31 Dec. 1930, reiterated longstanding Catholic teaching* that the primary purpose of the sexual organs is procreation of children, and anything against this (e.g., sodomy, contraception, etc.) is a sin against nature and intrinsically evil (Denzinger 2239):
But surely no reason, not even the gravest, can bring it about that what is intrinsically against nature becomes in accord with nature, and honorable. Since, moreover, the conjugal act by its very nature is destined for the generating of offspring, those who in the exercise of it deliberately deprive it of its natural force and power, act contrary to nature, and do something that is shameful and intrinsically bad.
*cf. Romans 1:26-27, that "men with men working that which is filthy" "is against nature" and "the natural use of the women"
His condemnation of contraception in that same encyclical is also infallible dogma pertaining to morals; cf. the "De moribus" section of this answer.
There is no dogma about the private property rights
It is a defined dogma that Jesus and the apostles possessed private property:
Pope John XXII Cum inter nonnullos 13 Nov. 1323 on the poverty of Christ (Denzinger 494):
[…] to affirm persistently that our Redeemer and Lord Jesus Christ and His apostles did not possess anything either in particular or even in common […] we […] declare […] shall henceforth be branded as erroneous and heretical, since it expressly contradicts Sacred Scripture, which in many passages asserts that they did have some possessions […]
And they had rights to the use, selling, or donating of said property:
Moreover, […] to affirm persistently that the right to use these same possessions which Sacred Scripture testifies that they had was by no means appropriate to our aforesaid Redeemer and His apostles, and that they did not have the right to sell or to donate them or to acquire others by means of them, which, nevertheless, Sacred Scripture testifies that they did […] is wicked, contrary to Sacred Scripture, and to Catholic doctrine about the use, actions, or deeds on the part of our Redeemer, the Son of God, we declare […] worthily branded as erroneous and heretical.