Shim, You-Jin;Choi, Kihang published 《Cyclic Ketals of Tartaric Acid: Simple and Tunable Reagents for the Determination of the Absolute Configuration of Primary Amines》 in 2010. The article was appeared in 《Organic Letters》. They have made some progress in their research.Quality Control of Dimethoxydiphenylmethane The article mentions the following:
2,2-Diphenyl-[1,3]dioxolane-4,5-dicarboxylic acid (DPD) and 2,2-dinaphthalen-2-yl-[1,3]dioxolane-4,5-dicarboxylic acid (DND) have been synthesized starting from di-Me tartrate. DPD and DND amides of α-chiral primary amines showed significantly different 1H chem. shift values depending on the stereochem. of the derivatizing agent. On the basis of this chem. shift difference, the absolute configuration of amine substrates could be assigned. DND amides showed significantly larger chem. shift differences than the corresponding DPD amides allowing for a more error-free assignment. And Dimethoxydiphenylmethane (cas: 2235-01-0) was used in the research process.
Dimethoxydiphenylmethane is one of ethers-buliding-blocks. Ethers feature bent C–O–C linkages. In dimethyl ether, the bond angle is 111° and C–O distances are 141 pm. The barrier to rotation about the C–O bonds is low. Quality Control of Dimethoxydiphenylmethane The bonding of oxygen in ethers, alcohols, and water is similar. In the language of valence bond theory, the hybridization at oxygen is sp3.
Reference:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem