The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Nuclear spin-spin relaxation》. Authors are Lipsicas, M.; Hartlang, A..The article about the compound:1,3,5,7-Tetramethyl-6-phenyl-2,4,8-trioxa-6-phosphaadamantanecas:97739-46-3,SMILESS:CC1(C2)OC(C3)(C)OC2(C)OC3(C)P1C4=CC=CC=C4).Reference of 1,3,5,7-Tetramethyl-6-phenyl-2,4,8-trioxa-6-phosphaadamantane. Through the article, more information about this compound (cas:97739-46-3) is conveyed.
The nuclear spin-spin relaxation time, T2, in H at 77.5°K., on a gas sample of approx. 100 Amagats d., was more accurately determined equal to the spin-lattice relaxation time, T1, within ±4%, correcting a previous report (CA 56, 4271h).
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Reference:
Tetrahydropyran – Wikipedia,
Tetrahydropyran – an overview | ScienceDirect Topics