40949-94-8Relevant articles and documents
Convenient method for the preparation of a solution of potassium bis(trimethylsilyl)amide
Magedov, I. V.,Polykarpov, A. Yu.,Zotova, T. O.,Smushkevich, Yu. I.,Drozd, V. N.
, p. 2197 - 2198 (1995)
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Formation of a hydride containing amido-zincate using pinacolborane
Ingleson, Michael J.,Nichol, Gary S.,Uzelac, Marina,Yuan, Kang
, p. 14018 - 14026 (2021/10/19)
Amido-zincates containing hydrides are underexplored yet potentially useful complexes. Attempts to access this type of zincate through combining amido-organo zincates and pinacolborane (HBPin)viaZn-C/H-BPin exchange led instead to preferential formation of amide-BPin and/or [amide-BPin(Y)]?(Y = Ph, amide, H), when the amide is hexamethyldisilazide or 2,2,6,6-tetramethylpiperidide and the hydrocarbyl group was phenyl or ethyl. In contrast, the use of a dipyridylamide (dpa) based arylzinc complex led to Zn-C/H-BPin metathesis being the major outcome. Independent synthesis and full characterisation of two LnLi[(dpa)ZnPh2] (L = THF,n= 3; L = PMDETA,n= 1) complexes,1and3, respectively, enabled reactivity studies that demonstrated that these species display zincate type reactivity (by comparison to the lower reactivity of the neutral complex (Me-dpa)ZnPh2,4, Me-dpa = 2,2′-dipyridyl-N-methylamine). This included1performing the rapid deprotonation of 4-ethynyltoluene and also phenyl transfer to α,α,α-trifluoroacetophenone in contrast to neutral complex4. Complex1reacted with one equivalent of HBPin to give predominantly PhBPin (ca.90%) and a lithium amidophenylzincate containing a hydride unit, complex7-A, as the major zinc containing product. Complex7-Atransfers hydride to an electrophile preferentially over phenyl, indicating it reacts as a hydridozincate. Attempts to react1with >1 equivalent of HBPin or with catecholborane led to more complex outcomes, which included significant borane and dpaZn substituent scrambling, two examples of which were crystallographically characterised. While this work provides proof of principle for Zn-C/H-BPin exchange as a route to form an amido-zincate containing a hydride, amido-organozincates that undergo more selective Zn-C/H-BPin exchange still are required.
Preparation of α-Fluorobis(phenylsulfonyl)methane (FBSM)
Prakash, G.K. Surya,Shao, Nan,Wang, Fang,Ni, Chuanfa
, p. 130 - 144 (2014/04/03)
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Crystalline 10,10-Bis((2-fluoro-4-pyridinyl)methyl)-9(10H)-Anthracenone and an improved process for preparing the same
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, (2008/06/13)
The present invention relates to processes for the synthesis of a crystalline polymorph of 10,10-Bis((2-fluoro-4-pyridinyl)methyl)-9(10H)-Anthracenone in high purity. The product is useful in the synthesis of pharmaceutical compounds for the reduction of cholinergic system dysfunction.