Carbene rearrangements. Part. 42. Intramolecular addition versus novel carbon-hydrogen bond insertion reactions of n-alkenyl-substituted cyclopropylidenes

Miebach, Thomas; Wüster, Hartmut; Brinker, Udo H.

doi:10.1021/jo00075a067

Cited by 11 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Actually the transformation is more complex, as was shown in a later investigation, at least at low temperatures. As demonstrated by Brinker [159] under these conditions besides, e.g. 1,2,7,8-nonatetraene ( 265 ), which is still the main product of the debromination/rearrangement, other hydrocarbons are formed, among them 267 , a formal 1,5-CH-insertion product, and 268 , which results by way of a 1,7-cycloelimination process (Scheme 63).…”

Section: Reviewmentioning

confidence: 89%

The chemistry of bisallenes

Hopf¹,

Μαρκόπουλος²

2012

Beilstein J. Org. Chem.

View full text Add to dashboard Cite

SummaryThis review describes the preparation, structural properties and the use of bisallenes in organic synthesis for the first time. All classes of compounds containing at least two allene moieties are considered, starting from simple conjugated bisallenes and ending with allenes in which the two cumulenic units are connected by complex polycyclic ring systems, heteroatoms and/or heteroatom-containing tethers. Preparatively the bisallenes are especially useful in isomerization and cycloaddition reactions of all kinds leading to the respective target molecules with high atom economy and often in high yield. Bisallenes are hence substrates for generating molecular complexity in a small number of steps (high step economy).

show abstract

Section: Reviewmentioning

confidence: 89%

The chemistry of bisallenes

Hopf¹,

Μαρκόπουλος²

2012

Beilstein J. Org. Chem.

View full text Add to dashboard Cite

show abstract

“…This was examined by Skattebøl, who reported the formation of a new compound in small yield . The experiment was repeated by McClusky 6 and by Meibach, Wüster, and Brinker, and the product was shown to be 2-vinylbicyclo[3.1.0]hexane ( 9 ) rather than the desired tricyclo[5.1.0.0 1,3 ]octane ( 4 ). Compound 9 was formed by insertion of the carbene into the allylic CH bond instead of addition to the CC double bond.…”

Section: Ring Expansionmentioning

confidence: 99%

Ring Expansion and Contraction of a Two-Carbon Bridged Spiropentane

Wiberg

Snoonian

1998

J. Org. Chem.

View full text Add to dashboard Cite

The reactions of tricyclo[4.1.0.01,3]heptan-4-one (5) and two related systems with diazomethane and m-CPBA were examined in order to determine the relative reactivity and migratory aptitudes for the three compounds. The reactions of 5 with diazomethane and m-CPBA yielded new derivatives of the tricyclo[5.1.0.01,3]octane ring system that showed that migration of cyclopropylcarbinyl is favored over cyclopropyl migration in this system. Photolysis of 5-diazotricyclo[4.1.0.01,3]heptan-4-one (23) in methanol and dimethylamine did not lead to ring contraction to the tricyclo[3.1.0.01,3]hexane ring system, but an interesting product was derived from an unusual rearrangement process in the photolysis in dimethylamine. Matrix photolysis of 23 at 15 K gave a decrease in the diazo band at 2085 cm-1 and the appearance of a new band at 2117 cm-1, which is a normal position expected for a small-ring ketene such as cyclopropylketene. Thus, matrix photolysis appears to have yielded a derivative of the previously unknown tricyclo[3.1.0.01,3]hexane ring system. The lithium enolate of 5 was characterized by NMR spectroscopy at −80 °C and was found to rearrange to m-cresol at −65 °C. The geometries of the bridged spiropentanes of this work were optimized at the MP2(frozen core)/6-31G* level of theory, and group equivalent values were derived in order to calculate the heats of formation for these compounds using the calculated energies.

show abstract

Allenic Hydrocarbons – Preparation and Use in Organic Synthesis

Hopf¹

2004

Modern Allene Chemistry

View full text Add to dashboard Cite

Carbene rearrangements. Part. 42. Intramolecular addition versus novel carbon-hydrogen bond insertion reactions of n-alkenyl-substituted cyclopropylidenes

Cited by 11 publications

References 0 publications

The chemistry of bisallenes

The chemistry of bisallenes

Ring Expansion and Contraction of a Two-Carbon Bridged Spiropentane

Allenic Hydrocarbons – Preparation and Use in Organic Synthesis

Contact Info

Product

Resources

About