68165-40-2Relevant academic research and scientific papers
Catalytic asymmetric [4+2]-cycloaddition of dienes with aldehydes
Liu, Luping,Kim, Hyejin,Xie, Youwei,Fares, Christophe,Kaib, Philip S.J.,Goddard, Richard,List, Benjamin
supporting information, p. 13656 - 13659 (2017/11/06)
Despite its significant potential, a general catalytic asymmetric [4+2]-cycloaddition of simple and electronically unbiased dienes with any type of aldehyde has long been unknown. Previously developed methodologies invariably require activated, electronically engineered substrates. We now provide a general solution to this problem. We show that highly acidic and confined imidodiphosphorimidates (IDPis) are extremely effective Br?nsted acid catalysts of the hetero-Diels-Alder reaction of a wide variety of aldehydes and dienes to give enantiomerically enriched dihydropyrans. Excellent stereoselectivity is generally observed and a variety of scents and natural products can be easily accessed.
A convenient approach for the synthesis of 1,3,5-trioxanes under solvent-free conditions at room temperature
Li, Xinzhong,Lin, Qi,Cao, Rong
, p. 1017 - 1022 (2014/06/09)
A series of environmentally benign bis-SO3H-functionalized Bronsted acidic ionic liquids were synthesized by using aliphatic polyamines and 1,3-propanesultone as the source chemicals. These ionic liquids acted as efficient inexpensive and recyclable catalysts for cyclotrimerization of aliphatic aldehydes at room temperature under solvent-free conditions. The reactions proceeded smoothly with good to excellent isolated yields (66.9-97.6 %=) and were generally complete in 1.5 h when the amount of ionic liquids was 0.1 mol%. The ionic liquids could be recovered readily and reused five times without any significant loss in their catalytic activity. Graphical abstract: [Figure not available: see fulltext.]
Novel acidic ionic liquids as efficient and recyclable catalysts for the cyclotrimerization of aldehydes
Song, Heyuan,Chen, Jing,Xia, Chungu,Li, Zhen
experimental part, p. 266 - 273 (2011/10/31)
A mild, efficient, and ecofriendly procedure for cyclotrimerization of aldehydes was realized by using a series of novel Brnsted acidic ionic liquids (BAILs) consisting of double-SO3H groups in cations as catalysts. Good conversion of aldehydes and selectivity of trialkyl-1,3,5-trioxanes were achieved by using 1mol% of BAILs. In addition, the catalyst system could be recycled and reused at least eight times without apparent loss of activity. Taylor & Francis Group, LLC.
Synthesis of 1,3,5-trioxanes: A new, simple method using a bentonitic earth as catalyst
Camarena,Cano,Delgado,Zuniga,Alvarez,Garcia
, p. 6857 - 6858 (2007/10/02)
A simple method for synthesizing aliphatic as well as aromatic 1,3,5-trioxanes using as catalyst a bentonitic earth is reported. The yields ranged from good to excellent.
