Browse
Submit Data
Databases
API
Help

Dataset Information

20 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Controlling, Understanding, and Redirecting the Thermal Rearrangement of 3,3-Dicyano-1,5-enynes.

ABSTRACT: The thermal [3,3] rearrangement of 3,3-dicyano-1,5-enynes to ?-allenyl alkylidenemalononitriles (the "enyne Cope rearrangement") has largely eluded synthetic value as the desired products, too, are thermally reactive and ultimately yield 6? electrocyclization products. Herein, we describe experimental and computational studies related to the thermal rearrangement of 1,5-enynes, structural features to halt the thermal rearrangement at the allene stage, and a reductive variant for preparing bifunctional allenyl malononitriles. We also describe various ways that the bifunctional building blocks can be manipulated and converted to cyclic and acyclic architectures.

SUBMITTER: Scott SK

PROVIDER: S-EPMC6679653 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Controlling, Understanding, and Redirecting the Thermal Rearrangement of 3,3-Dicyano-1,5-enynes.

Scott Sarah K SK Sanders Jacob N JN White Katherine E KE Yu Roland A RA Houk K N KN Grenning Alexander J AJ

Journal of the American Chemical Society 20181112 47

The thermal [3,3] rearrangement of 3,3-dicyano-1,5-enynes to γ-allenyl alkylidenemalononitriles (the "enyne Cope rearrangement") has largely eluded synthetic value as the desired products, too, are thermally reactive and ultimately yield 6π electrocyclization products. Herein, we describe experimental and computational studies related to the thermal rearrangement of 1,5-enynes, structural features to halt the thermal rearrangement at the allene stage, and a reductive variant for preparing bifunc ...[more]

PMID: 30379070

Similar Datasets

Transient [3,3] Cope rearrangement of 3,3-dicyano-1,5-dienes: computational analysis and 2-step synthesis of arylcycloheptanes.

Project description:A simple and modular route to arylcycloheptene scaffolds is reported. The two-step route from Knoevenagel adducts and allylic electrophiles is made possible through the design of a Cope rearrangement that utilizes a "traceless" activating group to promote an otherwise thermodynamically unfavorable transformation. Experimentally, the [3,3] rearrangement occurrs transiently at room temperature with a computed barrier of 19.5 kcal mol-1, which ultimately allows for three-component bis-allylation. Ring-closing metathesis delivers the arylcycloheptane and removes the activating group. This report describes the design and optimization of the methodology, scope and mechanistic studies, and computational analysis.

| S-EPMC6295866 | biostudies-literature

1,5-Dicyano-anthraquinone.

Project description:The complete mol-ecule of the title compound, C(16)H(6)N(2)O(2), which is generated by a crystallographic inversion centre, is almost planar (r.m.s. deviation = 0.04 Å). In the crystal, adjacent mol-ecules are stacked along the a axis, with a shortest centroid-centroid separation of 3.826 (2) Å.

| S-EPMC2983950 | biostudies-literature

Dimethyl 6,6'-dicyano-2,2'-bipyridine-3,3'-dicarboxyl-ate.

Project description:In the title compound, C(16)H(10)N(4)O(4), the two pyridine rings are twisted by 44.41?(2)° and the ester groups form dihedral angles of 48.77?(4) and 45.75?(2)° with the corresponding pyridine rings. The crystal structure is stabilized by inter-molecular C-H?O hydrogen bonds and ?-? stacking inter-actions between the pyridine rings [centroid-to-centroid distance 3.797?(2)?Å].

| S-EPMC2977680 | biostudies-literature

Dimethyl 3,3'-[(4,5-dicyano-1,2-phenyl-ene)bis-(-oxy)]dibenzoate.

Project description:In the title compound, C(24)H(16)N(2)O(6), the dihedral angles between the central 4,5-dicyano-1,2-phenyl-ene unit [maximum deviation from planarity = 0.014 (4) Å] and the pendant benzene rings are 73.62 (5) and 84.08 (6)°.

| S-EPMC3435642 | biostudies-literature

Gold-catalyzed enantioselective ring-expanding cycloisomerization of cyclopropylidene bearing 1,5-enynes.

Project description:An enantioselective ring-expanding cycloisomerization of 1,5-enynes bearing a cyclopropylidene moiety has been developed. This methodology provides a new approach to bicyclo[4.2.0]octanes, a structural motif present in many biologically active natural products.

| S-EPMC3998771 | biostudies-literature

Construction of 1,5-enynes by stereospecific Pd-catalyzed allyl-propargyl cross-couplings.

Project description:The palladium-catalyzed cross-coupling of chiral propargyl acetates and allyl boronates delivers chiral 1,5-enynes with excellent levels of chirality transfer and can be applied across a broad range of substrates.

| S-EPMC3374959 | biostudies-literature

Photochemical Radical Bicyclization of 1,5-Enynes: Divergent Synthesis of Fluorenes and Azepinones.

Project description:A dual nickel- and iridium-photocatalyzed radical cascade bicyclization reaction for the synthesis of highly complex molecular structures in an atom- and step-economic manner has been described. A series of radical precursors are utilized for the divergent synthesis of diversely substituted fluorenes and indenoazepinones bearing quaternary carbons by using cascade cyclization reactions of 1,5-enynes. This reaction is characterized by its mild conditions, broad substrate scope, excellent selectivity, and satisfactory yield including facile scale-up synthesis.

| S-EPMC10825824 | biostudies-literature

Borylation and rearrangement of alkynyloxiranes: a stereospecific route to substituted α-enynes.

Project description:1,3-Enynes are important building blocks in organic synthesis and also constitute the key motif in various bioactive natural products and functional materials. However, synthetic approaches to stereodefined substituted 1,3-enynes remain a challenge, as they are limited to Wittig and cross-coupling reactions. Herein, stereodefined 1,3-enynes, including tetrasubstituted ones, were straightforwardly synthesized from cis or trans-alkynylated oxiranes in good to excellent yields by a one-pot cascade process. The procedure relies on oxirane deprotonation, borylation and a stereospecific rearrangement of the so-formed alkynyloxiranyl borates. This stereospecific process overall transfers the cis or trans-stereochemistry of the starting alkynyloxiranes to the resulting 1,3-enynes.

| S-EPMC6604752 | biostudies-literature

Gold(i)-catalyzed addition of aldehydes to cyclopropylidene bearing 6-aryl-1,5-enynes.

Project description:A diastereoselective, gold-catalyzed cascading cycloisomerization of alkylidene cyclopropane bearing 1,5-enynes that terminates in a cyclo-addition of aldehydes has been developed. This diastereoselective reaction provides convergent access to novel polycyclic molecular structures (18 examples), and tolerates a diverse scope of aldehydes. Mechanistic studies reveal that the catalytic cycle rests at a digold off-cycle intermediate, one of which was isolated.

| S-EPMC5134929 | biostudies-literature

Understanding, controlling and optimising the cooling of waste thermal treatment beds including STARx Hottpads.

Project description:STARx (Self-sustaining Treatment for Active Remediation ex situ) is a thermal treatment strategy for contaminated soils and organic wastes. Key to this technology is that organics are embedded in porous matrix beds (e.g. sand). STARx induces a self-sustaining smouldering combustion front that traverses the bed, burning away the embedded contaminants/wastes. The time and cost effectiveness of this technology is largely dictated by the time required for cooling of the hot, clean, porous matrix bed that remains after treatment. This study is the first to explore the cooling of these beds. A suite of novel simulations investigated the influence of key parameters on bed-cooling time. The results reveal that cooling time decreased nearly linearly with decreases of volume-averaged bed temperature and bed bulk density. Increased injection air fluxes led to the non-linear decrease of cooling time. Also, cooling time was negatively impacted by bed temperature inhomogeneity, which influenced preferential air flow through cooler regions of the bed, bypassing hotter regions. From these results, using lower bulk density bed materials, increased air fluxes and enhancing wall insulation to improve bed temperature homogeneity were identified as system optimisations to reduce cooling times. While the aim of this research is to improve the STARx cooling process, the results are also highly applicable to many similar engineering systems that involve hot porous bed cooling.

| S-EPMC9393652 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data