Silver(I) ion catalyzed rearrangements of strained .sigma. bonds. XXIX. Influence of structural features on the course of transition metal catalyzed 1,8-bishomocubane rearrangements

Poly(polyhedral)s: synthesis and study of a new class of polyurethanes composed of homocubanes

“…The basketane diester 9 and diol 10 were rearranged to the corresponding snoutane derivatives ( 14 and 15 , respectively) in excellent yields using silver nitrate . NMR and IR spectra recorded for compounds 15 and 16 were consistent with the data reported in the literature . Compounds 14 , 17 and 18 constituted new compounds and were characterized using 1 H and 13 C NMR spectroscopy, FTIR spectroscopy, elemental analysis and mass spectrometry.…”

“…Homocubanes, such as basketane and snoutane, also feature polyhedral structures yet have been underutilized in polymeric materials . Due to their relatively low symmetries and compact structures, we hypothesized that the integration of these cage‐like compounds into the backbones of polymeric materials should enhance their intrinsic physical properties while retaining high solubility.…”

Synthesis of tetracyclo[6.3.0.04,11.05,9]undeca-2,6-diene, 10-oxatetracyclo[6.3.0.04,11.05,9]undeca-2,6-diene, and hexacyclo[5.4.0.02,6.04,11.05,9.08,10]undecane. Structure of syn-4, syn-7-diiodopentacyclo[6.3.0.02,6.03,10.05,9]undecane. Synthesis and rhodium(I)-promoted rearrangement

“…The plot of log [7a]o/[7a]t vs. time displayed considerable curvature. The rate data which we observed for this reaction can be compared directly with the corresponding rate data obtained for the [Rh(norbornadiene)Cl]2-catalyzed isomerization of cubane (for which k -14 M™1 s"x in CDCI3 solvent at 40 °C)!18 Additionally, it has been reported that the [Rh(norbornadiene)Cl]2-catalyzed isomerization of 9,10-dicarbomethoxy-l,8-bishomocubane at 40 °C in dry benzene is complete in 40 h. 19 Unexpectedly, compound 7a was found to be inert toward AgBF4 in chloroform solution (58-62 °C, 4 days) and toward AgCICL in benzene solution at 78 °C. Unreacted 7a could be recovered essentially quantitatively after 10 days' exposure to silver perchlorate at this temperature.…”

“…The major (less volatile) component was identified2 as hexacyclo[5.4.0.02'6.04'n.06'9.08 '10]undecane (5): mp 132-134 °C (sealed tube); ir (CC14) 3040 (s), 2960 (s), 2850 (m), 1438 (w), 1301 (m), 1290 (m), 1198 (w), 1015 (w), 950 (w), and 930 cm-1 (w); NMR (CDCla) 1.43 (d, J = ca. 1 Hz, 2 H, 3-methylene protons), 1.83-2.48 (complex multiplet, 4 ), 2.48-3.17 (complex multiplet, 6 H); mass spectrum m/e 144 (molecular ion, 81), 129 (45), 128 (30), 116 (18), 115 (19), 79 (100), 78 (98), 77 (32), 66 (97), 51 (18), and 38 (30); 13C NMR (see Table I The minor (more volatile) component of the mixture was identified as tetracyclo[6.3.0.04'u.05'9]undeca-2,6-diene ("homohypostrophene", 6a): mp 141.5-142.5 °C (sealed tube) (lit.22 mp 143.5-144.5 °C); ir (CC14) 3055 (m), 2950 (s), 2806 (m), 1325 (m), 1018 (m), and 835 cm"1 (m); NMR (CDCI3) 1.63 (br s, 2 H, 10methylene protons), 2.33 (br s, 4 H, 1,4,5,8-methine protons), 3.17 (m, 2 H, 9,11-methine protons), and 5.93 (s, 4 H, vinyl protons); mass spectrum m/e 144 (molecular ion, 12), 129 (8), 115 (9), 79 (100), 78 (32), 77 (31), and 66 (15). The 13C NMR spectrum of 6a (Table I) was identical with that of authentic material.…”

Surface photochemistry: Semiconductor mediated reactions of some saturated strained hydrocarbons

“…However, there was strong presumptive evidence suggesting that 2+ would rearrange to 7+. On Rh (1) and Pd(I1) complexes 2 was shown to yield 7 as the major product (18). Furthermore, substituted derivatives of 2 were shown to rearrange to the corresponding tricyclo-[4.2.2.0~*~]deca-3,7-diene by an electron transfer mechanism (5,19).…”