64871-66-5Relevant academic research and scientific papers
Asmic Isocyanide-Nitrile Isomerization-Alkylations
Alwedi, Embarek,Lujan-Montelongo, J. Armando,Cortés-Mejía, Rodrigo,del Campo, Jorge M.,Altundas, Bilal,Fleming, Fraser F.
supporting information, p. 4644 - 4648 (2019/07/31)
Anisylsulfanylmethylisocyanide, Asmic, is a versatile building block whose alkylations provide a range of substituted isocyanides. The anisylsulfanyl group plays a critical role in the sequenced deprotonation-alkylation and the subsequent sulfanyl-lithium exchange. Complexation of the anisylsulfanyl group to BuLi in the presence of TMEDA affords a lithiated isocyanide whose alkylations generate trisubstituted isocyanides. In the absence of TMEDA, BuLi triggers cyanide expulsion to afford a transient carbene; reorientation of cyanide with attack at the carbene affords a lithiated nitrile whose alkylations afford quaternary nitriles. The complexation-induced isocyanide-nitrile rearrangement is exceptionally facile, occurring within 5 min at –78 °C. Detailed mechanistic and computational analyses identify the importance of chelation in the bifurcating mechanism: internal chelation favors cyanide extrusion to form a carbene whereas chelating agents favor arylsulfanyl-lithium exchange to generate a lithiated isocyanide. The combined experimental and computational analyses reveal a new mechanism for isocyanide-nitrile isomerization which provides valuable insight for rapidly assembling substituted isocyanides.
Asmic: An Exceptional Building Block for Isocyanide Alkylations
Alwedi, Embarek,Lujan-Montelongo, J. Armando,Pitta, Bhaskar R.,Chao, Allen,Cortés-Mejía, Rodrigo,Del Campo, Jorge M.,Fleming, Fraser F.
supporting information, p. 5910 - 5913 (2018/09/21)
Asmic addresses the long-standing challenge of alkylating isocyanides, providing access to isocyanides with diverse substitution patterns. The o-anisylsulfanyl group serves a critical dual role by facilitating deprotonation-alkylation and providing a latent nucleophilic site through an unusual arylsulfanyl-lithium exchange.
Sulfone–Metal Exchange and Alkylation of Sulfonylnitriles
Yang, Xun,Nath, Dinesh,Gau, Michael R.,Steward, Omar W.,Fleming, Fraser F.
supporting information, p. 7257 - 7260 (2017/06/13)
The first general sulfone–metal exchange is described. Treating substituted 2-pyridylsulfonylacetonitriles with either BuLi or Bu3MgLi generates metalated nitriles that efficiently intercept a variety of electrophiles to afford quaternary nitriles. The 2-pyridylsulfone is critical for the sulfone–metal exchange because chelation anchors the organometallic proximal to the electrophilic, tetrasubstituted sulfone to override complex-induced deprotonation. Alkylating commercial 2-pyridinesulfonylacetonitrile with mild bases, either K2CO3 or DBU, and subsequent sulfone–metal exchange and alkylation rapidly assembles quaternary nitriles by three alkylations, only one of which requires an organometallic reagent.
Arylthio-metal exchange of α-arylthioalkanenitriles
Nath, Dinesh,Skilbeck, Melanie C.,Coldham, Iain,Fleming, Fraser F.
supporting information, p. 62 - 65 (2014/01/23)
The addition of BuLi, Bu3MgLi, Et2ZnBuLi, or Me 2CuLi to α-arylthioalkanenitriles triggers an arylthio-metal exchange. NMR spectroscopic analyses implicate organometallic attack on sulfur forming a three-coordinate sulfidate as the key intermediate. Electrophilic trapping affords tertiary and quaternary nitriles in high yield. The method addresses the challenge of improving the functional group tolerance and preventing polyalkylations.
Sulfinylnitriles: Sulfinyl-metal exchange-alkylation strategies
Nath, Dinesh,Fleming, Fraser F.
, p. 2023 - 2029 (2013/03/14)
Adding organolithiums, Grignard reagents, or zincates to sulfinylnitriles triggers a facile sulfinyl-metal exchange to afford N- or C-metalated nitriles. Sulfinyl-magnesium exchange-alkylations efficiently install quaternary and tertiary centers, even in
β-aryl nitrile construction via palladium-catalyzed decarboxylative benzylation of α-cyano aliphatic carboxylate salts
Shang, Rui,Huang, Zheng,Xiao, Xiao,Lu, Xi,Fu, Yao,Liu, Lei
supporting information, p. 2465 - 2472,8 (2020/08/31)
The palladium-catalyzed decarboxylative benzylation of α-cyano aliphatic carboxylate salts with benzyl electrophiles was discovered. This reaction exhibits good functional group compatibility and proceeds under relatively mild conditions. A diverse range of quaternary, tertiary and secondary β-aryl nitriles can be conveniently prepared by this method. Copyright
Nitrile alkylations through sulfinyl-metal exchange
Nath, Dinesh,Fleming, Fraser F.
, p. 11790 - 11793 (2012/01/06)
Triple alkylation: Phenylsulfinyl- and phenylthioacetonitrile can function as trianion equivalents of acetonitrile by sequential alkylation and sulfinyl-metal exchange (see scheme; mCPBA=meta-chloroperoxybenzoic acid). The metalated nitriles alkylate a range of electrophiles to obtain nitriles with quaternary centers. The sulfinyl-metal exchange proceeds under very mild conditions and has a high functional-group tolerance. Copyright
