Four existing and three new functionalized chromium terephthalates having MIL-101 topology and denoted as Cr-MIL-101-X (existing ones with X=–F, 1-F; –Cl, 2-Cl; –Br, 3-Br; –CH3, 4-CH3; new ones with X=–C6H4, 5-C6H4; –F2, 6-F2, –(CH3)2, 7-(CH3)2) were synthesized under hydrothermal conditions. All the materials except 5-C6H4 could be prepared by a general synthetic route, in which the mixtures of CrO3, H2BDC-X (BDC=1,4-benzenedicarboxylate) linkers, conc. HCl and water with a molar ratio of 1:1:3.9:222.2 were reacted at 180°C for 144h. Compared to the 144h of synthesis time, three of the compounds, namely 1-Cl, 2-Br and 5-C6H4, could be prepared in much shorter reaction times (12–18h at 180–210°C). The materials possess high thermal stability up to 270–300°C in an air atmosphere. The activated compounds exhibit significant porosity (SBET range: 1273–2135m2g−1). At 0°C and 1bar, the CO2 adsorption capacities of the compounds fall in the 1.7–2.9mmolg−1 range. Compounds 1-F and 6-F2 showed enhanced CO2 uptake values compared to parent Cr-MIL-101. The benzene adsorption capacities of the compounds lie in the range of 66.2–139.5molecules per unit cell at 50°C and p/p0=0.35. The increased benzene uptake value of 1-F compared to un-functionalized Cr-MIL-101 and 4-CH3 suggests that the fluorination has induced more hydrophobicity in Cr-MIL-101 as compared to the methylation.