Counterattack Mode Differential Acetylative Deprotection of Phenylmethyl Ethers: Applications to Solid Phase Organic Reactions
摘要:
A counterattack protocol for differential acetylative cleavage of phenylmethyl ether has been developed. The phenylmethyl moiety is liberated as benzyl bromide that is isolated and reused providing advantages in terms of waste minimization/utilization and atom economy. The applicability of this methodology has been extended for solid phase organic reactions with the feasibility of reuse of the solid support.
A Green, Solvent-Free, Microwave-Assisted, High-Yielding YbCl<sub>3</sub>Catalyzed Deprotection of THP/MOM/Ac/Ts Ethers of Chalcone Epoxide and 2′-Aminochalcone and Their Sequel Cyclization
作者:Sumit Kumar、Nishant Verma、Iram Parveen、Naseem Ahmed
DOI:10.1002/jhet.2517
日期:2016.11
Under microwave and solvent‐free conditions, YbCl3 efficiently catalyzed the deprotection of tetrahydropyran‐2‐yl, methoxymethyl (MOM), acetyl, and tosyl groups and sequelcyclization of chalconeepoxide to 2‐hydroxyindanone and 2′‐aminochalcone to aza‐flavanone. The reaction afforded the products in excellent yield (78–99%) at 850 W microwave heating within 1–5 min under eco‐friendly conditions. The
ASAAD, F. M., EGYPT. J. CHEM., 1982, 25, N 3, 293-300
作者:ASAAD, F. M.
DOI:——
日期:——
Counterattack Mode Differential Acetylative Deprotection of Phenylmethyl Ethers: Applications to Solid Phase Organic Reactions
作者:Asit K. Chakraborti、Sunay V. Chankeshwara
DOI:10.1021/jo801659g
日期:2009.2.6
A counterattack protocol for differential acetylative cleavage of phenylmethyl ether has been developed. The phenylmethyl moiety is liberated as benzyl bromide that is isolated and reused providing advantages in terms of waste minimization/utilization and atom economy. The applicability of this methodology has been extended for solid phase organic reactions with the feasibility of reuse of the solid support.
β-Cyclodextrin in water: highly facile biomimetic one pot deprotection of phenolic THP/MOM/Ac/Ts ethers and concomitant regioselective cyclization of chalcone epoxides and 2′-aminochalcones
作者:Sumit Kumar、Nishant Verma、Naseem Ahmed
DOI:10.1039/c5ra15996b
日期:——
A mild and efficient one-pot deprotection of THP/MOM/Ac/Tsethers and the concomitant cyclization of chalconeepoxides to 2-hydroxyindanones or 2′-aminochalcones to aza-flavanones using β-cyclodextrin in water has been developed. β-CD was found to be highly effective at carrying out the deprotection and sequential transformations in an eco-friendly environment affording moderate to excellent yields
已经开发了在水中使用β-环糊精对THP / MOM / Ac / Ts醚进行温和有效的一锅脱保护以及将查尔酮环氧化物伴随环化为2-羟基茚满酮或2'-氨基查耳酮为氮杂黄酮的过程。发现β-CD在生态友好的环境中进行脱保护和顺序转化非常有效,在60°C下8-22分钟内可提供中等至极好的收率(59-99%)。在该反应中首次使用了水,这是一种生态友好的反应介质。所提出的方案的优点包括高产率和催化剂的可重复使用性,并且该方案排除了金属和有机溶剂的使用。与先前报道的方法相比,本方法温和得多,但更先进。