936716-85-7Relevant academic research and scientific papers
Development of a photolabile carbonyl-protecting group toolbox
Yang, Haishen,Zhang, Xin,Zhou, Lei,Wang, Pengfei
experimental part, p. 2040 - 2048 (2011/05/06)
New salicyl alcohol derived photolabile carbonyl protecting groups have been developed, and the effect of substituents on the photochemical properties of photolabile protecting groups (PPGs) has been studied. The 3-(dimethylamino)phenyl groups at the α position prove to be important to the efficiency of the deprotection reactions, as shown in the photo reactions of the acetal 9. On the other hand, expansion of the salicyl alcohol's benzene skeleton to naphthalene does not improve the photochemical properties of PPGs. A neutral protecting protocol has been generalized to new PPGs with α,α-diaryl salicyl alcohol backbone. Thus, installation of PPGs onto aldehydes is readily achieved at 140 °C without using any other chemical reagents. These PPGs are stable under acidic conditions typical for hydrolyzing acetals and constitute orthogonal protecting groups with traditional 1,3-dioxane/1,3-dioxolane for carbonyl compounds. Highly efficient release of carbohydrate molecules is demonstrated, which can be potentially useful in site-specific release and immobilization of carbohydrates for preparation of high-density microarrays. With the enriched PPG toolbox, PPGs are divided into three subgroups based on their UV absorption profiles. PPGs from different subgroups can be sequentially removed by using different UV irradiation wavelengths. For PPGs absorbing UVA (λ >315 nm), photochemical deprotection can be carried out with sunlight in high yields.
Oxidation with a photolabile carbonyl protecting group
Yang, Haishen,Mu, Feng,Wang, Pengfei
scheme or table, p. 8955 - 8961 (2011/12/15)
A novel oxidation approach utilizing a robust photolabile carbonyl protecting group reagent (1) as the oxidizing reagent has been developed. Different from existing methods, this approach oxidizes primary alcohols to the photosensitive acetals (e.g., 3), providing another unique approach to the protected aldehydes. Thus, for the first time, oxidation and protection are achieved in one reaction. Secondary alcohols are oxidized to the corresponding ketones. Moreover, the photolabile protecting group (PPG) also oxidizes ethers and esters. The oxidation is presumably via hydride abstraction by the tritylium ion generated from 1 under acidic conditions. However, the mechanisms for primary alcohols and secondary alcohols are slightly different.
Installation of photolabile carbonyl-protecting groups under neutral conditions without using any other chemical reagents
Wang, Pengfei,Wang, Yun,Hu, Ayou,Liang, Xing
experimental part, p. 208 - 211 (2009/06/21)
Methods of installing photolabile protecting groups for carbonyl compounds under neutral conditions without using any other chemical reagents are described. Wiley-VCH Verlag GmbH & Co. KGaA, 2009.
Novel photolabile protecting group for carbonyl compounds
Pengfei, Wang,Huayou, Hu,Yun, Wang
, p. 1533 - 1535 (2008/02/02)
Equation presented A novel type of photo-protecting group for carbonyl compounds is described. The protecting group is readily accessed in one step from commercially available material. Installation of the protecting group upon the carbonyl compounds is achieved in excellent yields. The carbonyl compounds in their protected form are remarkably stable under various conditions and can be released photochemically in high efficiency.
