27262-60-8Relevant articles and documents
Ethyl Lithiodiazoacetate: Extremely Unstable Intermediate Handled Efficiently in Flow
Müller, Simon T. R.,Hokamp, Tobias,Ehrmann, Svenja,Hellier, Paul,Wirth, Thomas
, p. 11940 - 11942 (2016)
Ethyl diazoacetate (EDA) is one of the most prominent diazo reagents. It is frequently used in metal–carbene-type reactions. However, EDA can also be used as a nucleophile under base catalysis. Whilst the addition of EDA to aldehydes can be performed using organic bases, the addition of EDA to other carbonyl electrophiles requires the use of organometallics such as lithium diisopropylamide (LDA). The generated ethyl lithiodiazoacetate is highly reactive and decomposes rapidly, even at low temperatures. Herein, we report a continuous flow protocol that overcomes the problems associated with the instantaneous decomposition of ethyl lithiodiazoacetate. The addition of ethyl lithiodiazoacetate to ketones provides direct access to tertiary diazoalcohols in good yields.
Visible-light-driven radical 1,3-addition of selenosulfonates to vinyldiazo compounds
Li, Weiyu,Zhou, Lei
supporting information, p. 6652 - 6658 (2021/09/10)
Herein, we report a visible-light-driven radical 1,3-selenosulfonylation of vinyldiazo compounds with selenosulfonates, providing various γ-seleno allylic sulfones in good yields. This photochemical reaction was carried out at room temperature in an open flask using ethyl acetate as the solvent without any photocatalysts or additives. The control experiments corroborated that the 1,3-addition proceeded via a radical-chain propagation process. The synthetic applications of the resulting products were demonstrated by deselenization, reduction, bromination and allylation.
Copper-Catalyzed Oxy-Alkynylation of Diazo Compounds with Hypervalent Iodine Reagents
Hari, Durga Prasad,Waser, Jerome
supporting information, p. 2190 - 2193 (2016/03/08)
Alkynes have found widespread applications in synthetic chemistry, biology, and materials sciences. In recent years, methods based on electrophilic alkynylation with hypervalent iodine reagents have made acetylene synthesis more flexible and efficient, but they lead to the formation of one equivalent of an iodoarene as side-product. Herein, a more efficient strategy involving a copper-catalyzed oxy-alkynylation of diazo compounds with ethynylbenziodoxol(on)e (EBX) reagents is described, which proceeds with generation of nitrogen gas as the only waste. This reaction is remarkable for its broad scope in both EBX reagents and diazo compounds. In addition, vinyl diazo compounds gave enynes selectively as single geometric isomers. The functional groups introduced during the transformation served as easy handles to access useful building blocks for synthetic and medicinal chemistry.
