14469-83-1Relevant articles and documents
NaBH4 in N-methylpyrrolidone: a safe alternative for hydride displacement reaction.
Torisawa,Nishi,Minamikawa
, p. 2787 - 2789 (2001)
Enhanced reactivity of NaBH4 was observed as a solution in N-methylpyrrolidone (NMP). Thus, a simple protocol for debromination of alkyl bromide and sulfonate is devised with NMP as a key solvent. Also described is a new mixed borohydride system, NaBH4-LiOTf-NMP, which works as an alternative to NaBH3CN for the SN2 type displacement. No reports have ever revealed usefulness of NMP in borohydride reduction.
Self-assembling properties of non-ionic tetraphenylporphyrins and discotic phthalocyanines carrying oligo(ethylene oxide) alkyl or alkoxy units
Kroon, Johannes M.,Koehorst, Robert B. M.,Van Dijk, Marinus,Sanders, Georgine M.,Sudhoelter, Ernst J. R.
, p. 615 - 624 (1997)
The thermotropic phase behaviour and self-assembling features of some non-ionic tetraphenylporphyrins and phthalocyanines containing oligo(ethylene oxide) alkoxy or alkyl units have been investigated. From DSC measurements and polarization microscopy it was concluded that none of the tetraphenylporphyrins was mesomorphic while the phthalocyanines displayed discotic hexagonal phases even at room temperature. The aggregation of the compounds in aqueous media was studied by means of UV-VIS and fluorescence spectroscopy and it has been found that in water the tetraphenylporphyrins form J- or head-to-tail type of aggregates while phthalocyanines form H- or face-to-face type of aggregates. The luminescence properties of the tetraphenylporphyrin and phthalocyanine aggregates are explained on the basis of the molecular exciton approximation. Steric constraints and orientational disorder in the tetraphenylporphyrin aggregates determine the luminescence yield relative to the monomeric species. The cofacial arrangement of the macrocycles in phthalocyanine aggregates results in a forbidden S1-S0 transition and thus in a complete disappearance of the luminescence.
Substrate and Catalyst Effects in the Enantioselective Copper-Catalysed C–H Insertion Reactions of α-Diazo-β-oxo Sulfones
Shiely, Amy E.,Clarke, Leslie-Ann,Flynn, Christopher J.,Buckley, Aoife M.,Ford, Alan,Lawrence, Simon E.,Maguire, Anita R.
supporting information, p. 2277 - 2289 (2018/06/04)
Excellent enantioselectivities of up to 98 % ee are achieved by employing the copper-bis(oxazoline)-NaBARF catalyst system in the C–H insertion reactions of α-diazo-β-oxo sulfones. The influence of variation of the bis(oxazoline) ligand, copper salt, additive and substrate on both the efficiency and the enantioselectivities of these intramolecular C–H insertion reactions has been explored. Optimum enantioselectivities are achieved with phenyl and diphenyl ligands across the substrate series.
Redox-Active Esters in Fe-Catalyzed C-C Coupling
Toriyama, Fumihiko,Cornella, Josep,Wimmer, Laurin,Chen, Tie-Gen,Dixon, Darryl D.,Creech, Gardner,Baran, Phil S.
, p. 11132 - 11135 (2016/10/12)
Cross-couplings of alkyl halides and organometallic species based on single electron transfer using Ni and Fe catalyst systems have been studied extensively, and separately, for decades. Here we demonstrate the first couplings of redox-active esters (both isolated and derived in situ from carboxylic acids) with organozinc and organomagnesium species using an Fe-based catalyst system originally developed for alkyl halides. This work is placed in context by showing a direct comparison with a Ni catalyst for >40 examples spanning a range of primary, secondary, and tertiary substrates. This new C-C coupling is scalable and sustainable, and it exhibits a number of clear advantages in several cases over its Ni-based counterpart.
