139706-47-1Relevant articles and documents
Hafnium Triflate as a Highly Potent Catalyst for Regio- and Chemoselective Deprotection of Silyl Ethers
Zheng, Xiu-An,Kong, Rui,Huang, Hua-Shan,Wei, Jing-Ying,Chen, Ji-Zong,Gong, Shan-Shan,Sun, Qi
, p. 944 - 953 (2019/02/10)
As a Group IVB transition metal Lewis acid, hafnium triflate [Hf(OTf) 4 ] exhibited exceptionally high potency in desilylations. Since the amounts of Hf(OTf) 4 required for the deprotection of 1°, 2°, 3° alkyl and aryl tert -butyldimethylsilyl (TBS) ethers are significantly different, ranging from 0.05 mol% to 3 mol%, regioselective deprotection of TBS could be easily implemented. Moreover, chemoselective cleavage of different silyl ethers or removal of TBS in the presence of most hydroxyl protecting groups was also accomplished. NMR analyses of silyl products from TBS deprotection indicated that Hf(OTf) 4 -catalyzed desilylation may proceed via different mechanisms, depending on the solvent used.
NOVEL CRYPTOPHYCIN COMPOUNDS AND CONJUGATES, THEIR PREPARATION AND THEIR THERAPEUTIC USE
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Page/Page column 211; 214-215, (2017/06/30)
The present invention relates to cryptophycin compounds of formula (I). The invention also relates to cryptophycin payloads, to cryptophycin conjugates, to compositions containing them and to their therapeutic use, especially as anticancer agents. The inv
Fluorous TBAF: A convenient and selective reagent for fluoride-mediated deprotections
Fustero, Santos,Sancho, Amador Garcia,Acena, Jose Luis,Sanz-Cervera, Juan F.
supporting information; experimental part, p. 6398 - 6401 (2009/12/06)
(Chemical Equation Presented) A fluorous analogue of TBAF has been developed for its use in the clean removal of silicon-derived protecting groups. Purification of the crude mixtures by fluorous solid-phase extractions allowed alcohols, amines, and carboxylic acids to be obtained in high purity, with no need of chromatographic separations. The moderate reactivity of fluorous TBAF was exploited in selective deprotections of several bifunctional molecules.