93-96-9Relevant articles and documents
Gold(i)-catalysed dehydrative formation of ethers from benzylic alcohols and phenols
Veenboer, Richard M. P.,Nolan, Steven P.
, p. 3819 - 3825 (2015)
We report the cross-dehydrative reaction of two alcohols to form unsymmetrical ethers using NHC-gold(i) complexes (NHC = N-heterocyclic carbene). Our progress in developing this reaction into a straightforward procedure is discussed in detail. The optimised methodology proceeds under mild reaction conditions and produces water as the sole by-product. The synthetic utility of this environmentally benign methodology is exemplified by the formation of a range of new ethers from readily available phenols bearing electron withdrawing substituents and secondary benzylic alcohols with various substituents. Finally, we present experimental results to account for the chemoselectivity obtained in these reactions.
An expedient, efficient and solvent-free synthesis of T3P-mediated amidation of benzhydrols with poorly reactive N-nucleophiles under MW irradiation
Cheruku, Srinivas,Manikyanally, Kumara N.,Mantelingu, Kempegowda,Nagarakere, Sandhya C.,Narayana, Yatheesh,Rangappa, Kanchugarakoppal S.,Sunilkumar, Makanahalli P.
, p. 4421 - 4426 (2022/03/14)
An expedient, efficient, economical, environmentally benign, and solvent free amidation protocol of benzhydrols with less reactive nitrogen nucleophiles assisted by propylphosphonic anhydride (T3P) under microwave irradiation has been developed. The methodology has been deployed for a wide range of heterocycles and electron-withdrawing & electron-donating groups. The protocol resulted in good to excellent yields under the given conditions (26 examples, 68-93% yield).
Iodine catalysed synthesis of unsymmetrical benzylic ethers by direct cross-coupling of alcohols
Kharrngi, Balamphrang,Basumatary, Grace,Bez, Ghanashyam
, (2021/09/13)
Although symmetrical ethers can be synthesized easily from alcohols, synthesis of unsymmetrical ethers by dehydrative cross-coupling of alcohols is still a challenge. While dehydrative cross-coupling is environmentally appealing due to formation of water as the only byproduct, the chances for formation of symmetrical ethers always exist. The existing transition metal based methods give good selectivity, but the catalyst are costly and not readily available. Here, we present a simple, readily available, and cost-effective catalyst in the form of molecular iodine which catalyzes a highly selective cross-coupling of benzylic alcohols with benzyl, alkyl, and aryl alcohols to give their corresponding unsymmetrical ethers in good to excellent yield.
Direct Nucleophilic Substitution of Alcohols Using an Immobilized Oxovanadium Catalyst
Nishio, Tomoya,Yoshioka, Shin,Hasegawa, Kai,Yahata, Kenzo,Kanomata, Kyohei,Akai, Shuji
supporting information, p. 4417 - 4422 (2021/07/16)
Direct nucleophilic substitution of alcohols with thiols or carbon nucleophiles was achieved using a mesoporous silica-supported oxovanadium catalyst (VMPS4). Benzyl and allyl alcohols were compatible in this reaction under mild conditions, affording the products in high yields. The VMPS4 catalyst showed excellent chemoselectivity toward alcohols in the presence of acid-labile functional groups, which is in contrast to that observed for the commonly used Lewis acid catalysts, which exhibit poor selectivity. The VMPS4 catalyst could be recycled by simple centrifugation, and the catalytic activity was maintained over seven cycles.
