80017-20-5Relevant academic research and scientific papers
Chiral 1,3,2-Diazaphospholenes as Catalytic Molecular Hydrides for Enantioselective Conjugate Reductions
Miaskiewicz, Solène,Reed, John H.,Donets, Pavel A.,Oliveira, Caio C.,Cramer, Nicolai
supporting information, p. 4039 - 4042 (2018/03/13)
Secondary 1,3,2-diazaphospholenes have a polarized P?H bond and are emerging as molecular hydrides. Herein, a class of chiral, conformationally restricted methoxy-1,3,2-diazaphospholene catalysts is reported. We demonstrate their catalytic potential in asymmetric 1,4-reductions of α,β-unsaturated carbonyl derivatives, including enones, acyl pyrroles, and amides, which proceeded in enantioselectivities of up to 95.5:4.5 e.r.
High-temperature synthesis of amides from alcohols or aldehydes by using flow chemistry
Ambreen, Nida,Wirth, Thomas
, p. 7590 - 7593 (2015/04/22)
An efficient conversion of aliphatic and aromatic alcohols or aldehydes into the corresponding primary amides was successfully achieved by using flow chemistry. Excellent yields were obtained in very short reaction times, and thus this method offers an efficient alternative to traditional methods for amide formation.
Green oxidative synthesis of primary amides from primary alcohols or aldehydes catalyzed by a cryptomelane-type manganese oxide-based octahedral molecular sieve, OMS-2
Yamaguchi, Kazuya,Kobayashi, Hiroaki,Wang, Ye,Oishi, Takamichi,Ogasawara, Yoshiyuki,Mizuno, Noritaka
, p. 318 - 327 (2013/03/14)
In this study, a new green synthetic route to primary amides, that is, aerobic oxidative amidation of primary alcohols or aldehydes with ammonia, has been developed. In the presence of a cryptomelane-type manganese oxide-based octahedral molecular sieve (OMS-2), various kinds of structurally diverse primary alcohols or aldehydes including aromatic, olefinic, heteroaromatic, and aliphatic ones can be converted into the corresponding primary amides in moderate to high yields (20 examples from primary alcohols and 11 examples from aldehydes). Furthermore, gram-scale amidation is also effective, and the analytically pure primary amides can easily be isolated. The present catalysis by OMS-2 is truly heterogeneous in nature, and the retrieved OMS-2 catalyst can be reused several times (at least 12 times for the amidation of 2-pyridinemethanol). Though the formation rates of the corresponding primary amide are gradually decreased by repeating reuse experiments, OMS-2 can be regenerated by calcination. The present OMS-2-catalyzed amidation of primary alcohols is composed of four relay steps: (i) oxidative dehydrogenation of primary alcohols, (ii) dehydrative condensation of aldehydes with ammonia, (iii) oxidative dehydrogenation of aldimines, and (iv) hydration of nitriles to form the corresponding primary amides. All steps (i)-(iv) can be promoted by the presence of OMS-2. The Royal Society of Chemistry 2013.
Catalyzed dehydrogenative coupling of primary alcohols with water, methanol, or amines
Zweifel, Theo,Naubron, Jean-Valere,Gruetzmacher, Hansjoerg
supporting information; experimental part, p. 559 - 563 (2009/04/14)
A working partnership: Metal-ligand cooperativity is responsible for the high activity of the rhodium amido complex 1 in the dehydrogenative coupling of primary alcohols with water, methanol, or amines, including ammonia (see scheme), to give carboxylic acids, methyl carboxylates, or amides, respectively. The catalysis proceeds under mild reaction conditions in the presence of a recyclable hydrogen acceptor A. The multistep mechanism was elucidated by computational methods. (Chemical Equation Presented)
