Sato, Kikumasa et al. published their research in Chemistry Letters in 1981 | CAS: 13417-49-7

5,6-Dihydro-2H-pyran-3-carbaldehyde (cas: 13417-49-7) belongs to tetrahydropyran derivatives. In organic synthesis, the 2-tetrahydropyranyl group is used as a protecting group for alcohols. The reaction of tertiary 1,4- and 1,5-diols with cerium ammonium nitrate at room temperature gives tetrahydrofuran and tetrahydropyran derivatives in high yield and stereoselectivity. Various fragrant compounds have been synthesized using this method.SDS of cas: 13417-49-7

Stereospecific synthesis of (±)-β-santalol was written by Sato, Kikumasa;Miyamoto, Osamu;Inoue, Seiichi;Honda, Kiyoshi. And the article was included in Chemistry Letters in 1981.SDS of cas: 13417-49-7 This article mentions the following:

BrCH2CH2CH:CMeCH2OAc, obtained in 4 steps from 5,6-dihydro-2H-pyran-2-carboxaldehyde, reacted with the bicycloheptanecarboxylate I to give II, (R = CO2Et, R1 = Ac), whose reduction with (Me2CHCH2)2AlH followed by bromination and LiAlH4 reduction of II (R = CH2Br, R1 = Ac) gave (±)-β-santalol (II, R = Me, R1 = H). In the experiment, the researchers used many compounds, for example, 5,6-Dihydro-2H-pyran-3-carbaldehyde (cas: 13417-49-7SDS of cas: 13417-49-7).

5,6-Dihydro-2H-pyran-3-carbaldehyde (cas: 13417-49-7) belongs to tetrahydropyran derivatives. In organic synthesis, the 2-tetrahydropyranyl group is used as a protecting group for alcohols. The reaction of tertiary 1,4- and 1,5-diols with cerium ammonium nitrate at room temperature gives tetrahydrofuran and tetrahydropyran derivatives in high yield and stereoselectivity. Various fragrant compounds have been synthesized using this method.SDS of cas: 13417-49-7

Referemce:
Tetrahydropyran – Wikipedia,
Tetrahydropyran – an overview | ScienceDirect Topics