Crystal structure of a tris(2-amino-eth-yl)methane capped carbamoyl-methyl-phosphine oxide compound.

The mol-ecular structure of the tripodal carbamoyl-methyl-phosphine oxide compound diethyl {[(5-[2-(di-eth-oxy-phosphor-yl)acetamido]-3-{2-[2-(di-eth-oxy-phos-phor-yl)acetamido]-eth-yl}pent-yl)carbamo-yl]meth-yl}phospho-nate, C 25 H 52 N 3 O 12 P 3 , features six intra-molecular hydrogen-bonding inter-actions. The phospho-nate groups have key bond lengths ranging from 1.4696 (12) to 1.4729 (12) Å (P=O), 1.5681 (11) to 1.5811 (12) Å (P-O) and 1.7881 (16) to 1.7936 (16) Å (P-C). Each amide group adopts a nearly perfect trans geometry, and the geometry around each phophorus atom resembles a slightly distorted tetra-hedron.