The Pentanedioic acid,2,2,4-trimethyl-4-phosphono-, with the CAS registry number 67718-84-7, is also known as 2,2,4-Trimethyl-4-phosphonoglutaric acid. This chemical's molecular formula is C₈H₁₅O₇P and molecular weight is 254.17. What's more, its systematic name is 2,2,4-Trimethyl-4-phosphonopentanedioic acid and its EINECS number is 266-980-9. 

Physical properties of Pentanedioic acid,2,2,4-trimethyl-4-phosphono- are: (1)ACD/LogP: -1.74; (2)# of Rule of 5 Violations: 0; (3)ACD/LogD (pH 5.5): -6.66; (4)ACD/LogD (pH 7.4): -7.52; (5)ACD/BCF (pH 5.5): 1; (6)ACD/BCF (pH 7.4): 1; (7)ACD/KOC (pH 5.5): 1; (8)ACD/KOC (pH 7.4): 1; (9)#H bond acceptors: 7; (10)#H bond donors: 4; (11)#Freely Rotating Bonds: 5; (12)Polar Surface Area: 97.94 Å²; (13)Index of Refraction: 1.528; (14)Molar Refractivity: 52.11 cm³; (15)Molar Volume: 169 cm³; (16)Polarizability: 20.66×10^-24 cm³; (17)Surface Tension: 70.3 dyne/cm; (18)Density: 1.503 g/cm³; (19)Flash Point: 258.4 °C; (20)Enthalpy of Vaporization: 84.61 kJ/mol; (21)Boiling Point: 503.6 °C at 760 mmHg; (22)Vapour Pressure: 1.65E-11 mmHg at 25°C.

Preparation: this chemical can be prepared by tetraethyl 2,4,4-trimethyl-2-phosphonopentanedioate by heating. This reaction will need reagent conc. HCl with the reaction time of 24 hours and the yield is about 69%.

You can still convert the following datas into molecular structure:
(1)Canonical SMILES: CC(C)(CC(C)(C(=O)O)P(=O)(O)O)C(=O)O
(2)InChI: InChI=1S/C8H15O7P/c1-7(2,5(9)10)4-8(3,6(11)12)16(13,14)15/h4H2,1-3H3,(H,9,10)(H,11,12)(H2,13,14,15)
(3)InChIKey: KEJHHNKGPJZSNN-UHFFFAOYSA-N