乙烯基亚甲基环状碳酸酯(VMCC)的串联烯丙胺化/氧杂迈克尔加成已被开发出来,可通过单一钯催化或钯-有机物中继催化构建杂环。在此过程中,双亲核基团首先发生区域选择性烯丙胺化,然后第二个亲核基团进一步完成杂迈克尔加成反应,形成一系列杂环。其中,在钯-有机物中继催化下,可以以中高产率制备手性3,4-二氢-2H-苯并[ b ][1,4]恶嗪,且具有良好的对映选择性。
A series of propargylic tertiary alcohols decorated with an sp2-hybridised nitrogen donor were kinetically resolved by reagent-controlled dehydrogenative SiâO coupling with a strained, highly reactive silicon-stereogenic cyclic silane.
has been developed toward a range of carbocycles. The key success is based on the use of a batch of newly designed cyclic carbonates as substrates that can provide carbon–carbon zwitterion intermediate under palladium catalysis. The kinetics of the reactions are controllable toward either strained seven- or thermodynamically more favored five-membered carbocycles. The release of this chemistry will
β-Silyl-Assisted Tandem Diels–Alder/Nazarov Reaction of 1-Aryl-3-(trimethylsilyl) Ynones
作者:Rachael A. Carmichael、Punyanuch Sophanpanichkul、Wesley A. Chalifoux
DOI:10.1021/acs.orglett.7b00911
日期:2017.5.19
A one-pot tandem Diels–Alder/Nazarov reaction of 1-aryl-3-(trimethylsilyl) ynones has been achieved to generate carbo- and heterocyclic fused ring systems in good to excellent yields. The β-silyl effect is instrumental in accessing this otherwise challenging cascade annulation reaction. The tandem reaction proceeds in the presence of BCl3 to generate three new carbon–carbon bonds, a quaternary carbon
One-Pot Three-Step Synthesis of 1,2,3-Triazoles by Copper-Catalyzed Cycloaddition of Azides with Alkynes formed by a Sonogashira Cross-Coupling and Desilylation
作者:Frédéric Friscourt、Geert-Jan Boons
DOI:10.1021/ol1022036
日期:2010.11.5
A microwave-assisted, one-pot, three-step Sonogashira cross-coupling-desilylation-cycloaddition sequence was developed for the convenient preparation of 1,4-disubstituted 1,2,3-triazoles starting from a range of halides, acyl chlorides, ethynyltrimethylsilane, and azides.