Compounds of the formula ##STR1## WHEREIN Z is alkyl with 2 to 6 carbon atoms, x is oxygen, NH or sulfur, n and m are integers from 2 to 6, r is zero or 1, R.sup.4, R.sup.5 R.sup.6 and R.sup.7 are hydrogen or methyl and R.sup.3 is methyl, ethyl or phenyl. They are obtained by reacting 1 mole of a compound of formulaZ--(X--H).sub.nwith n.m moles of an alkyleneoxide or alkylenecarbonate of the formulas ##STR2## and n(m+r) moles of a phospholane of formula ##STR3## These compounds are used as flameproofing agents especially for pile carpets.