<sup>1</sup>H NMR Chemical Shift Changes as a Result of Introduction of Carbonyl-Containing Protecting Groups Observed in Bornol and Isoborneol
Baohe Lyu,
Honoka Sako,
Mio Sugiura,
Yoshikazu Hiraga,
Ryukichi Takagi,
Satomi Niwayama
Affiliations
Baohe Lyu
Graduate School of Science and Technology, Hiroshima Institute of Technology, 2-1-1 Miyake, Saeki-ku, Hiroshima 731-5193, Japan
Honoka Sako
Graduate School of Science and Technology, Hiroshima Institute of Technology, 2-1-1 Miyake, Saeki-ku, Hiroshima 731-5193, Japan
Mio Sugiura
Graduate School of Science and Technology, Hiroshima Institute of Technology, 2-1-1 Miyake, Saeki-ku, Hiroshima 731-5193, Japan
Yoshikazu Hiraga
Graduate School of Science and Technology, Hiroshima Institute of Technology, 2-1-1 Miyake, Saeki-ku, Hiroshima 731-5193, Japan
Ryukichi Takagi
Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan
Satomi Niwayama
Graduate School of Engineering, Muroran Institute of Technology, 27-1, Mizumoto-cho, Muroran 050-8585, Japan
Complete assignments of the 1H NMR chemical shifts for monoterpenes, borneol, and isoborneol, and their derivatives in which the secondary hydroxy group is protected with an acetyl group or a benzoyl group, have been made in CDCl3 and C6D6. Upon the protection of the hydroxy group with the carbonyl functional groups, or acetyl or benzoyl groups, many protons constituting the bicyclic ring exhibited downfield and upfield shifts in the chemical shift values, aiding in the unambiguous assignments of protons and carbons.
