2-((1,1-Dioxidohexahydro-3,5-methanocyclopenta[C][1,2]oxathiol-7-YL)oxy)-2-oxoethyl methacrylate
[CAS 1135824-87-1]

Identification

• Classification: Organic raw materials >> Carboxylic compounds and derivatives >> Carboxylic esters and their derivatives
• Name: 2-((1,1-Dioxidohexahydro-3,5-methanocyclopenta[C][1,2]oxathiol-7-YL)oxy)-2-oxoethyl methacrylate
• Synonyms: [2-[(5,5-dioxo-4-oxa-5λ6-thiatricyclo[4.2.1.03,7]nonan-2-yl)oxy]-2-oxoethyl] 2-methylprop-2-enoate
• Molecular Formula: C₁₃H₁₆O₇S
• Molecular Weight: 316.33
• CAS Registry Number: 1135824-87-1
• SMILES: CC(=C)C(=O)OCC(=O)OC1C2CC3C1OS(=O)(=O)C3C2

Properties

• Density: Density

chemBlink Chemical Story

CAS 1135824-87-1, often indexed under the short designation SNBMA, is a specialized methacrylate whose structure immediately reveals why it belongs to advanced polymer chemistry. One end of the molecule is a methacrylate group: its carbon-carbon double bond can undergo radical polymerization and become part of a polymer backbone. The other end is a compact, oxygen-rich bicyclic sulfone-containing group. Joining those two functions in one monomer lets a materials chemist build a polymer and simultaneously install a highly structured side chain rather than adding a separate low-molecular-weight modifier.

That design is especially relevant to photoresist chemistry. A modern chemically amplified resist is not simply a light-sensitive dye dissolved in an inert binder. The polymer itself helps determine film formation, glass transition, polarity, interaction with developer, transport of photo-generated acid, and the mechanical integrity of the patterned feature. Methacrylate monomers became important platforms because their polymerization is well understood and because many different side groups can be attached to the ester. Rigid alicyclic groups are particularly useful when a resist must combine low molecular motion with sufficient transparency and controlled dissolution behavior.

SNBMA illustrates this molecular-engineering strategy in an unusually compact way. Its methacrylate double bond provides the polymerizable handle, while the bridged cyclic group introduces rigidity and several heteroatoms, including a sulfone-like S(VI) center. Those features can alter polarity and free volume in the resulting polymer and therefore influence how a thin film responds to processing. The exact performance depends on copolymer composition, molecular weight, photoacid generator, bake conditions and developer, so the isolated monomer should not be assigned a single universal lithographic performance number.

Public literature devoted specifically to CAS 1135824-87-1 is limited, and much of the available information is found in specialty-chemical records rather than a large body of stand-alone papers. That limitation is itself informative. Semiconductor materials frequently depend on monomers and additives that are important as components of proprietary formulations even though they are not famous compounds in general chemical literature.

The useful story of SNBMA is therefore structural rather than commercial: one molecular fragment is chosen because it polymerizes reliably, while the other is chosen because it changes the behavior of the solid film. At nanometer dimensions, such side-chain decisions can influence whether an exposed resist develops cleanly or loses contrast through excessive motion, diffusion or swelling. A formidable systematic name thus describes a simple materials idea - build the processing function directly into the monomer.

References:
1. ChemicalBook, CAS 1135824-87-1, identity and structure record for SNBMA.
2. Ito H. Chemical amplification resists: history and development within microlithography. Adv Polym Sci. 2005;172:37-245.
3. Willson CG, Ito H, Frechet JMJ, Tessier TG, Houlihan FM. Approaches to the design of radiation-sensitive polymeric imaging systems with improved sensitivity. J Electrochem Soc. 1986;133:181-187.

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