The 3-Methyltetrahydrophthalic anhydride , with the CAS register number 5333-84-6, has other names as 1,3-Isobenzofurandione, 3a,4,7,7a-tetrahydro-4-methyl- , 4-Methyl-3a,4,7,7a-tetrahydro-2-benzofuran-1,3-dione , Maleicanhydrideand1,3-pentadieneadduct , and so on.

     The properties of 3-Methyltetrahydrophthalic anhydride : (1)H bond acceptors: 3 ; (2)Polar Surface Area: 43.37 ?2 ; (3)Index of Refraction: 1.507 ; (4)Molar Refractivity: 41.12 cm³ ; (5)Molar Volume: 138 cm³ ; (6)Polarizability: 16.3 ×10-24cm³ ; (7)Surface Tension: 38.4 dyne/cm ; (8)Density: 1.204 g/cm³ ; (9)Flash Point: 142.9 °C ; (10)Enthalpy of Vaporization: 54.32 kJ/mol ; (11)Boiling Point: 303 °C at 760 mmHg ; (12) Vapour Pressure: 0.000957 mmHg at 25°C .

     This kind of chemical is white solid, and belongs to the category of Diels-Alder Adducts, bicyclo-Diels-Alder adduct. It is usually used in the laborary to as the lab chemical reagent and intermediate. As it is being an irritant chemical to eyes, respiratory system and skin, remember be very carefull while using this kind of chemical. Please do as the following instructions: Wear suitable protective clothing, gloves and eye/face protection. If in case of contact with eyes, rinse immediately with plenty of water and seek medical advice.

     It is also used in producing other chemical substance while doing some Product distribution. Prepare the chemical reagent hydrogen and catalyst Ni/Al2O3, and then put this chemical in the reagent and then let it react with 2.0 hours under 200 ℃. Then you could get the product 3-methyl-hexahydrophthalic anhydride ,4-methyl-3a,4,7,7a-tetrahydro-isobenzofuran-1,3-dione ,3-methyl-D3-tetrahydrophthalic anhydride , and 3-methyl-phthalic acid anhydride. And the productivity is up to 72.2 %.

     In addition, if you need the molecular structure, you could convert the following data to get it:
SMILES:
O=C2OC(=O)C1C2/C=C\CC1CCopyCopied
InChI:
InChI=1/C9H10O3/c1-5-3-2-4-6-7(5)9(11)12-8(6)10/h2,4-7H,3H2,1H3