35583-17-6Relevant academic research and scientific papers
Introduction of axial chirality at a spiro carbon atom in the synthesis of pentaerythritol-imine macrocycles
Grajewski,Piotrowska,Zgorzelak,Janiak,Biniek-Antosiak,Rychlewska,Gawronski
, p. 981 - 987 (2018)
Novel chiral macrocyclic polyimines with spiro carbon atoms are described. The key feature of the synthesis is the formation of an axially chiral quaternary carbon atom having four constitutionally identical substituents. This is possible either by the freezing of the labile conformation of a spiro-diboronate moiety or by the diastereomeric fitting of a conformationally stable spiro-acetal moiety into a chiral framework. A general model for the description of this type of axial chirality is proposed.
A green recyclable poly(4-vinylpyridine)-supported copper iodide nanoparticle catalyst for the chemoselective synthesis of pentaerythritol diacetals from aromatic aldehydes
Albadi, Jalal,Iravani, Nasir,Dehghan, Farzaneh,Shirinic, Farhad
, p. 610 - 611,2 (2020/09/16)
Poly(4-vinylpyridine)-supported copper(I) iodide nanoparticles have been used as an efficient, green recyclable catalyst for the chemoselective synthesis of pentaerythritol diacetals from aromatic aldehydes and pentaerythritol under solvent-free conditions. This catalyst was reused six times without any loss of its activity.
Acetalation of pentaerithritol catalyzed by an Al-pillared saponite
Kannan,Sreekumar,Gil,Vicente
experimental part, p. 1118 - 1122 (2012/06/18)
Acetalation of pentaerithritol has been carried out in the presence of an Al-pillared saponite. Several carbonyl compounds were used, including aldehydes and ketones. Yields between 72 and 93% were obtained in all cases, except in the case of veratraldehyde where the carbonyl group was blocked. The high conversion could be explained by diffusion effects of intermediates and electronic effects between the reactants in the transition state. The catalyst was found to be active after three cycles.
N-bromosuccinimide (NBS) catalyzed highly chemoselective acetalization of carbonyl compounds using silylated diols and pentaerythritol under neutral aprotic conditions
Karimi, Babak,Hazarkhani, Hassan,Maleki, Jafar
, p. 279 - 285 (2007/10/03)
Various types of carbonyl compounds are efficiently converted to their 1,3-dioxanes and pentaerythritol diacetals by the use of either 1,3-bistrimethylsiloxy propane (A) or 1,3-bistrimethylsilanyloxy-2,2- bistrimethylsilanyloxymethyl propane (D) and a catalytic amount of N-bromosuccinimide (3-10 mol%) under essentially neutral aprotic condition, respectively. A variety of functionalities such as both aliphatic and phenolic -OTBDMS, -OMe, -OBz, furan ring, double bonds and more significantly phenolic -OTHP survived under the present reaction condition. The efficient conversion of two α-tertiary ketones to their cyclic acetals was also achieved using the present protocol.
New applications of solid silica chloride (SiO2-Cl) in organic synthesis. Efficient preparation of diacetals of 2,2-bis(hydroxymethyl)-1,3-propanediol from different substrates and their transthioacetalization reactions. Efficient regeneration of carbonyl compounds from acetals and acylals
Firouzabadi, Habib,Iranpoor, Nasser,Hazarkhani, Hassan
, p. 2847 - 2858 (2007/10/03)
A new application of solid silica chloride, an easily available and efficient catalyst for the preparation of diacetal of 2,2-bis-(hydroxymethyl)-1,3-propanediol from aldehydes, acetals, acylals, and oximes, is described. Transthioacetalization of diacetals of 2,2-bis-(hydroxymethyl)-1,3-propanediol into their corresponding 1,3-dithianes and 1,3-dithiolanes in the presence of silica chloride is presented. Efficient regeneration of carbonyl compounds from their corresponding acetals, ketals, diacetals, and acylals in the presence of this catalyst also is described.
