Aniline mediated oxidative C–C bond cleavage of α-alkoxy aldehydes in air and a model reaction for the synthesis of α-(d)-amino acid derivatives
作者:Bin Hu、Yunfeng Li、Zhongjun Li、Xiangbao Meng
DOI:10.1039/c3ob40685g
日期:——
4-methyl aniline mediated method for the oxidativeC–C bond cleavage has been developed. The reaction proceeds in airusing molecular oxygen as the oxidant, affording one-carbon shortened esters in moderate to good yields within a short time. Moreover, it provides a model reaction for the highly enantioselective synthesis of (D)-serine esters by combining with a L-proline catalyzed Mannich reaction.
Acid-Induced Rearrangement Reactions of α-Hydroxy-1,3-dithianes
作者:Karsten Krohn、Stephan Cludius-Brandt
DOI:10.1055/s-0029-1218658
日期:2010.4
Secondary benzylic or aliphatic α-hydroxydithianes 1a-c rearrange to α-thioketones when treated with acid. Related tertiary alcohols 1d-g eliminate to dithioketene ketals (e.g., 2d), which are ring-opened to thiols in some cases (1e, 1f). Allylic α-hydroxydithianes 1h and 1i form the thioesters 2h and 2i (homologation), and the tertiary alcohols 1j and 1k undergo deoxygenation to 2j and 2k. 1,3-dithianes
Lewis Base Catalyzed 1,3-Dithiane Addition to Carbonyl Compounds Using 2-Trimethylsilyl-1,3-dithiane
作者:Makoto Michida、Teruaki Mukaiyama
DOI:10.1246/cl.2008.26
日期:2008.1.5
1,3-Dithiane addition to various aldehydes and ketones using 2-trimethylsilyl-1,3-dithiane in the presence of a catalytic amount of a Lewis base such as tetrabutylammonium phenoxide (PhONn-Bu4) proceeds smoothly to afford the corresponding α-hydroxy dithiane compounds in good to high yields under mild conditions.
P(i-PrNCH2CH2)3N: an efficient catalyst for TMS-1,3-dithiane addition to aldehydes
作者:Kuldeep Wadhwa、John G. Verkade
DOI:10.1016/j.tetlet.2009.05.010
日期:2009.7
Herein we report the use of commercially available P(i-PrNCH2CH2)3N (1a) as an efficientcatalyst for 2-trimethylsilyl-1,3-dithiane (TMS–dithiane) addition to aldehydes at room temperature. The catalyst loading required for these reactions (5 mol %) is the lowest recorded in the literature, and the majority of the reaction times for this transformation are the shortest thus far reported. A variety
Anomalous C−C Bond Cleavage in Sulfur-Centered Cation Radicals Containing a Vicinal Hydroxy Group
作者:Zaiguo Li、Andrei G. Kutateladze
DOI:10.1021/jo035001z
日期:2003.10.1
1,3-dithianyl cationradicals having alpha-hydroxy-neopentyl or similar groups in position 2, which are generated via oxidative photoinducedelectrontransfer, undergo anomalous fragmentation necessitating refinement of the accepted mechanism. Experimental and computational data support a rationale in which proton abstraction from the hydroxy group in the initial cationradical does not cause a Grob-like