Electron transfer reactions of aliphatic esters to the corresponding aliphatic ketones by lithium, 4,4′-di-t-butylbiphenyl radical anion
作者:Rafik Karaman、James L. Fry
DOI:10.1016/s0040-4039(01)80547-5
日期:1989.1
Sonication of some representative aliphatic esters with lithium in the presence of catalytic amounts of 4,4′-di-t-butylbiphenyl (DBB) in dry THF under N2 afforded the corresponding aliphaticketones in good yields. Monitoring studies by GC/MS and 1H-NMR spectroscopy after quenching indicate the intermediacy of the corresponding β-ketoesters.
N-Heterocyclic carbene-catalyzed asymmetric construction of cyclopentenones using enals and α-diketones is achieved, furnishing a series of highly functionalized cyclopentenones in a highly diastereo- and enantioselective manner. The protocol tolerates substrates with both aromatic and aliphatic groups, and further transformations of the products delivered a range of value-added molecules.
Carbonylation of organomagnesium compounds: catalysis by hexamethylphosphoric triamide
作者:Wilhelmus J. J. M. Sprangers、Robert Louw
DOI:10.1039/p29760001895
日期:——
(hydroxy)ketone derivatives [(1), (4), and (5)] from primary alkyl halides are outlined. Other types of R(Mg)X mostly lead to acyloins RCH(OH)C(O)R. Evidence for the formation of RCOMgX, or equivalent(s), as ‘first’ intermediates is presented. The overall mechanism is discussed. Products, and effects of HMPT on rate and product composition, can satisfactorily be explained via nucleophilic addition and substitution
Compositions and Methods for Fermentation of Biomass
申请人:Parekh Sarad
公开号:US20100268000A1
公开(公告)日:2010-10-21
In one aspect, this invention relates to production of useful fermentation end-products from biomass through simultaneous hydrolysis and fermentation by a microorganism, such as
Clostridium phytofermentans
. The invention also relates to the development of a process for efficient pretreatment and conversion of lignocellulosic biomass to end-products with high conversion efficiency (yield). In another aspect, methods for producing a fermentation end-product by fermenting hexose (C6) and pentose (C5) sugars with a microorganism, such as
Clostridium phytofermentans
are disclosed herein.