4-Methylene-1- bicyclo hexane,

In several preparations of deuterium labeled analogs, elimination of deuterium bromide was much slower than that of hydrogen bromide, suggesting an EicB mechanism for the elimination. Thus, in the preparation of cis- and rans -l,2-dimethyl-3-methylenecyclopropane (17), formation of the dideuteromethylene analogs took 7 days at room temperature, as opposed to 14 hours for the unlabeled compounds. In the case of endo- and exo-2-methyl-6-methylene-bicyclo[3.1.0]hexane (19), the dideutero analog also required heating to 45°C to complete the reaction. ... 

Methyl-6-methylen-octen-(2) (II) geht bei der mit Benzophenon, Fluorenon oder 2-Acetyl-naphthalin sensibilisierten Reaktion in das 5,5-Dimethyl-l-vinyl-bicyclo[2.1.1] hexan (III 75 % d.Th.) iiber1. Bei direkter Belichtung in Afcher entstehen nur 3% dieses Produkts und dafiir das 6,6-Dimethyl-2-methylen-bicyclo[3.1.1]heplan (IV fi-Pinen 14-16% d.Th.) und l-l4-Methyl-penten-[3)-yl]-cyclobuten (V 81-83% d.Th.)2 ... 

Oxymercuration followed by borohydride reduction of 6-methylenebicyclo-[3,l,l]heptane (166) gave the alcohols shown in Scheme 8. Similar reaction with 5-methylenebicyclo[2,l,l]hexane gave entirely monocyclic products. Stereochemical aspects are discussed for the formation and reduction of epoxides of 2-methylene- and 3-methylene-bicyclo[3,l,l]heptanes, the hydrobora-tion-oxidation of 3-methylenebicyclo[3,l,l]heptanes, and reduction by lithium aluminium hydride and diborane of bicyclo[3,l,l]heptanones. ... 

Die Solvolyse von Bicyclo(3.1.0)hexan-l-methyl-p-nitrobenzoat (158) wurde von Closson-and. Kwiatkowski untersucht (118), und dabei uberwiegend das 3-Methylen-cyclohexanol (159) gefunden. (158) reagiert 600mal schneller als... 

CsHjo Cyclohexene, methylcyclopentene, methylene cyclopentane, bicyclo--[3.1.0]-hexane, 2-methyl-1, 4-pentadiene 16.0-18.1 g, m, p 927... 

The Simmons-Smith reaction with cyclopenten-4-ol gives exclusively the cis isomer of bicyclo[3.1.0]hexan-3-ol (94, 540, 541). Cleavage of the Simmons-Smith reagent by the hydroxyl group would give a salt (VI), and intramolecular methylene transfer would then yield m-bicyclo-[3.1.0]hexan-3-ol after hydrolysis (42). An alternative mechanism was... 

Bicyclo 3.1.0 hexan 6-Methylen-E19b, 5241T. (Ringverengerung)... 

Bicyclo 3.2.0]hept-2-en 7-Hydroxy-1,4,4-trimethyl- E17e, 365 (subst. Bicyclo[4.1,0]hept-2-en/hv) Bicyclo 3.1.0[hexan 2-Oxo-1,5,6,6 (or 4,4,6,6)-tetramethyl- E17a, 861 (subst. 3-Oxo-cyclohexen/hv) Bicyclo(4.3.0]nonan 2-Hydroxy-8-methylen- E21c, 3041 (S02 —... 

In a more detailed investigation, it was found that the metallacyclobutane intermediate 4, on treatment with dimethyl sulfoxide, additionally regenerated the tetracyclic starting material in small amounts. When heating the primary complex in chloroform, 2-methylene-4-vinyl-bicyclo[3.1.0]hexane was the major decomplexation product. Reaction of the platinacyclo-butane 4 with diazomethane gave 2,4-divinylbicyclo[3.1.0]hexane and the tetracyclic starting material. ... 

Bicyclo[2.1.0]pentane-5-spirocyclopropane, Bicyclo[3.2.0]-hept-1-ene, 5-Methylenebicyclo[2.1.1]hexane, 1,2,6-Heptatriene, 3-Methylene-1,5-hexadiene and Tricyclo[4.1.0.0 ]heptane... 

The methylenecyclobutane rearrangement also appears to proceed via biradicals since the dimethyl products described above equilibrate prior to rearrangement to the other methylenecyclobutane. Interestingly, the extent of the formation of the ultimate product, 3-methylene-l,5-hexadiene, from the methylenecyclobutane rearrangement of bicyclo[3.2.0]hept-l-ene varied inversely with pressure suggesting that it was produced from vibrationally hot methylenebicyclo[2.1.1]hexane. 

Octatetraene, 3,4-Dimethylene-1,5-hexadiene, Bicyclo[4.2.0]hexa-1,5-diene, 1,2-Divinylcyclobutene, 2,3-Dimethylenebicyclo[2.2.0]hexane, 1,4-Ethano-2-methylene-spiropentane, 1 -Allyl-2-vinylcyclopropene... 

Updated Entry replacing T-02142 4-Methylene-I- l-methylethyl)bicyclo[3.1.0]hexane, 9CI. 1-Isopropyl-4-methylenebicyclo[3.1.0]hexane. Sabinene [3387-41-5]... 

---