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61.
M. J. Musmar Gary E. Martin Robert T. Gampe Milton L. Lee Ralph E. Hurd Marvin L. Tedjamulia Hirotaka Kudo Raymond N. Castle 《Journal of heterocyclic chemistry》1985,22(1):219-223
Total assignment of the 13C-nmr spectrum of the helical molecule phenanthro[4,3-a]dibenzothiophene at 125.762 MHz is reported. Assignments were made by the combined application of 13C-13C autocorrelated double quantum coherence and heteronuclear relayed coherence transfer (RELAY) experiments. 相似文献
62.
Aileen Pfleider Halverson Lyle W. Castle Raymond N. Castle 《Journal of heterocyclic chemistry》1996,33(1):179-183
Naphtho[1′,2′:4,5]thieno[2,3-c][1,10]phenanthroline and naphtho[2′,1′:4,5]thieno[2,3-c][1,10]phenanthroline, two novel polycyclic heterocyclic ring systems, have been synthesized in four steps from known starting materials. The total 1H nmr spectral assignments were made using a COSY experiment to identify the spin systems. 相似文献
63.
Yoshinori Tominaga Raymond N. Castle Milton L. Lee 《Journal of heterocyclic chemistry》1982,19(5):1125-1130
Two pentacyclic thiophenes, benzo[4,5]phenaleno[1,9–6c]thiophene ( 1 ) and benzo[4,5]phenaleno[9,1-bc]-thiophene (2) were synthesized via the corresponding 3-methylphenanthro[2,1-b]thiophene (7) and 1-methylanthra[2,1–6]thiphene ( 19 ). 相似文献
64.
Yoshinori Tominaga Milton L. Lee Raymond N. Castle 《Journal of heterocyclic chemistry》1981,18(5):967-972
All isomers of the parent anthra[b]thiophenes and benzo[b]naphtho[d]thiophenes, namely anthra[2,3-b]thio-phene, anthra[2,1-b]thiophene, anthra[1,2-b]thiophene, benzo[b]naphtho[2,3-d]thiophene, benzo[b]naphtho[2,1-d]thiophene and benzo[b]naphtho[1,2-d]thiophene were synthesized using a new procedure. 相似文献
65.
Yoshinori Tominaga Lyle W. Castle Raymond N. Castle 《Journal of heterocyclic chemistry》1996,33(4):1319-1321
Photocyclization of the substituted 2-([1]benzothien-3-yl)-3-phenylpropenoic acids 3a-c in the presence of iodine and air in a benzene-cyclohexane mixture afforded a separable mixture of three compounds, benzo[b]naphtho[2,1-d]thiophene-6-carboxylic acids 4a-c , 6H-benzo[b]naphtho[2,3-d]thiopyran-6-ones 5a-c , and 10-methoxy-2-methyl-6H-benzo[b]naphtho[2,3-d]pyran-6-one ( 6 ). 相似文献
66.
The synthesis of both isomers of benzo[1,2]phenaleno[bc]thiophene namely, benzo[1,2]phenaleno[3,4-bc]-thiophene and benzo[1,2]phenaleno[4,3-bc]thiophene is described. 相似文献
67.
[reaction: see text] Alpha-nitro ketones can be transformed selectively into trialkyl-substituted pyrazines via reaction with alpha-amino ketones using octyl viologen as an electron-transfer reagent. The new synthetic method, and the optimal reaction conditions that allow for the regiochemical control, are described. 相似文献
68.
[reaction: see text] Total synthesis of the alkaloid (+/-)-hasubanonine is described. A key feature of the route is generation of a phenanthrene intermediate via a Suzuki coupling-Wittig olefination-ring-closing metathesis sequence. Conversion of the phenanthrene into the target molecule required six steps including dearomatization by means of oxidative phenolic coupling, anionic oxy-Cope rearrangement, and a final acid-promoted cyclization. Production of an undesired rearranged product in the last step could be suppressed by moderating the acid strength. 相似文献
69.
B. E. Richter J. C. Kuei L. W. Castle B. A. Jones J. S. Bradshaw M. L. Lee 《Chromatographia》1983,17(10):570-573
Summary Crosslinkable cyanopropylpolysiloxane stationary phases have been difficult to produce because of steric effects of the large cyanopropyl groups or because of the interaction between the polar cyanopropyl groups and the groups added for crosslinking. Various polymers containing 50% to 90% cyanopropyl were synthesized which contained vinyl,p-tolyl, or 4-vinylphenyl groups for crosslinking. Thep-tolyl group was found to give satisfactory crosslinking if there were two such groups attached to one silicon atom. 相似文献
70.
The present study attempts to develop a detailed numerical approach and a simulation procedure to predict the motion of gas, ions and particles inside a simple parallel plate channel containing a single corona wire. A hybrid Finite Element (FEM)-Flux Corrected Transport (FCT)-Finite Volume (FVM) method is used: the FEM–FCT numerical algorithm is applied for modeling the steady-state corona discharge, while the turbulent gas flow and the particle motion under electrostatic forces are modeled using the commercial CFD code FLUENT. Calculations for the gas flow are carried out by solving the Reynolds-averaged Navier–Stokes equations and turbulence is modeled using the k–? turbulence model. An additional source term is added to the gas flow equation to include the effect of the electric field, obtained by solving a coupled system of the electric field and charge transport equations using User-Defined Functions (UDFs). The particle phase is simulated based on the Lagrangian approach, where a large number of particles is traced with their motion affected by the gas flow and electrostatic forces using the Discrete Phase Model (DPM) in FLUENT. The developed model is useful to gain insight into the particle collection phenomena that take place inside an ESP. 相似文献