Reactive intermediates in the bicyclo[3.1.0]hexyl and bicyclo[3.1.0]hexylidene systems. III. The addition of hydrogen chloride and deuterium chloride to bicyclo[3.1.0]hex-2-ene

Inductive and Resonance Effects of Substituents on π-Face Selection

“…Incorporation of the stereogenic center into the cyclopropane ring introduces the endocyclic C−C bond in the α-position whose σ CC orbital is higher in energy and more diffuse than the σ CC orbital of a nonstrained aliphatic C−C bond. A number of reactions of bicyclo(2.1.0)pent-2-ene , and bicyclo(3.1.0)hex-2-ene, Scheme , − suggest that the cyclopropyl group promotes anti approach more effectively than a comparable alkyl group . However, examination of the stereochemistry of metal hydride reductions of bicyclo(3.1.0)hexen-2-one derivatives, Scheme , reveals that the π-face preference may also be opposite in these reactions, depending on the properties of the reducing agents .…”

Reaction of tetramethylhydrazine with iodine

“…This method was used successfully in the determination of the constant of the 1:1 complex of triethylamine and iodine. 11 The equilibrium constant for a 1:1 complex was estimated from the curves in Figure 2 by assuming that the decrease in intensity of the 520-µ band represented the iodine used up by complex formation. The value thus obtained was 4.5 ± 1.7 X 102 l./mol (25°).…”

Carbene Fragmentation in the Bicyclo[3.1.0]hexyl System: Disconnecting the Trishomocyclopropenyl Cation

“…The signature 1 H NMR signals of 11 and 12 are those of the protons α to Cl: (δ, CDCl 3 ) 4.53 ( 11 ) and 4.40 ( 12 ) [lit . δ 4.35 (CCl 4 ), lit .…”

“…The identities and distributions of products 9 − 13 were established by GC−MS, 1 H NMR, 13 C NMR, and NMR spiking experiments with independently prepared samples. Chlorides 9 and 10 were obtained in a ratio of 80:20 from the reaction of cis -3-bicyclo[3.1.0]hexanol with SOCl 2 and pyridine in ether. , Chlorides 11 and 12 were similarly 7 prepared in a 1.1:1 ratio from cis -2-bicyclo[3.1.0]hexanol. − 2-Bicyclo[3.1.0]hexene ( 13 ) was identified by its olefinic proton resonances at δ 5.30 and 5.87 . Finally, 14 and 15 were recognized by their low-field proton resonances (OOC H and OC H Cl 2 ) at δ 7.92 ( 14 ) and 7.15 ( 15 ).…”