TY - JOUR
T1 - Taming the reactivity of alkyl azides by intramolecular hydrogen bonding
T2 - Site-selective conjugation of unhindered diazides
AU - Maegawa, Koshiro
AU - Tanimoto, Hiroki
AU - Onishi, Seiji
AU - Tomohiro, Takenori
AU - Morimoto, Tsumoru
AU - Kakiuchi, Kiyomi
N1 - Publisher Copyright:
© the Partner Organisations.
PY - 2021/10/21
Y1 - 2021/10/21
N2 - Organic azides are still in the center of click chemistry connecting two molecules. However, taming the conjugation selectivity of azides is difficult without the help of bulky groups. We report herein the unique reactivities of α-azido secondary acetamides (α-AzSAs) as minimal and unhindered azide structures. The NH-azide interaction in the α-AzSAs, supposed by DFT calculations, allowed selective conjugation in the presence of other azido moieties, even without steric hindrance. With Staudinger-Bertozzi ligation, α-AzSAs underwent conjugation prior to the other primary alkyl azides. On the other hand, in propargyl cation-mediated triazole synthesis, other alkyl azides, including tertiary alkyl azides, underwent the conjugation faster than α-AzSAs. We also demonstrated site-selective integration of the functional components onto the diazide modular hubs.
AB - Organic azides are still in the center of click chemistry connecting two molecules. However, taming the conjugation selectivity of azides is difficult without the help of bulky groups. We report herein the unique reactivities of α-azido secondary acetamides (α-AzSAs) as minimal and unhindered azide structures. The NH-azide interaction in the α-AzSAs, supposed by DFT calculations, allowed selective conjugation in the presence of other azido moieties, even without steric hindrance. With Staudinger-Bertozzi ligation, α-AzSAs underwent conjugation prior to the other primary alkyl azides. On the other hand, in propargyl cation-mediated triazole synthesis, other alkyl azides, including tertiary alkyl azides, underwent the conjugation faster than α-AzSAs. We also demonstrated site-selective integration of the functional components onto the diazide modular hubs.
UR - http://www.scopus.com/inward/record.url?scp=85117411557&partnerID=8YFLogxK
U2 - 10.1039/d1qo01088c
DO - 10.1039/d1qo01088c
M3 - 学術論文
AN - SCOPUS:85117411557
SN - 2052-4110
VL - 8
SP - 5793
EP - 5803
JO - Organic Chemistry Frontiers
JF - Organic Chemistry Frontiers
IS - 20
ER -