154502-68-8Relevant academic research and scientific papers
Cooperative Catalysis for the Highly Diastereo- and Enantioselective [4+3]-Cycloannulation of ortho-Quinone Methides and Carbonyl Ylides
Loui, Henning Jakob,Schneider, Christoph,Suneja, Arun
supporting information, p. 5536 - 5540 (2020/02/05)
We describe herein a highly diastereo- and enantioselective [4+3]-cycloannulation of ortho-quinone methides and carbonyl ylides to furnish functionalized oxa-bridged dibenzooxacines with excellent yields and stereoselectivity in a single synthetic step. The combination of rhodium and chiral phosphoric acid catalysis working in concert to generate both transient intermediates in situ provides direct access to complex bicyclic products with two quaternary and one tertiary stereogenic centers. The products may be further functionalized into valuable and enantiomerically highly enriched building blocks.
A novel tandem [2 + 2] cycloaddition-Dieckmann condensation with ynolate anions. Efficient synthesis of substituted cycloalkenones and naphthalenes via formal [n + 1] cycloaddition
Shindo,Sato,Shishido
, p. 7818 - 7824 (2007/10/03)
A novel tandem [2 + 2] cycloaddition-Dieckmann condensation via ynolate anions is described. Ynolate anions are useful for the formation of reactive β-lactone enolates via a pathway not involving the enolization of the corresponding β-lactones. The [2 + 2] cycloaddition of ynolate anions with δ- or σ-keto esters, followed by Dieckmann condensation, gives bicyclic β-lactones, which are easily decarboxylated to produce synthetically useful 2,3-disubstituted cyclopentenones and cyclohexenones in one pot. This tandem reaction was applied to a novel, one-pot synthesis of highly substituted naphthalenes.
A new synthesis of 3-isochromanone derivatives based on the reaction of o-acylbenzyllithiums with ethyl chloroformate
Kobayashi,Mannami,Kawakita,Tokimatsu,Konishi
, p. 582 - 585 (2007/10/02)
A new method for the preparation of 3-isochromanone derivatives is reported. The method consists of the ethoxycarbonylation of o-acylbenzyllithiums with ethyl chloroformate and the subsequent NaBH4 reduction of the resulting o-acylphenylacetic
