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Palladium Catalyzed Coupling Reactions: Mechanism of Reductive Elimination. Progress Report, October 1, 1979-September 30, 1980. [Ethane Elimination] (open access)

Palladium Catalyzed Coupling Reactions: Mechanism of Reductive Elimination. Progress Report, October 1, 1979-September 30, 1980. [Ethane Elimination]

The 1,1-reductive elimination of ethane from three cis-bis(phosphine)-dimethylpalladium complexes, L/sub 2/Pd(CH/sub 3/)/sub 2/ (L = PPh/sub 3/, PPh/sub 2/,CH/sub 3/ and L/sub 2/ = Ph/sub 2/PCH/sub 2/CH/sub 2/PPh/sub 2/), and three trans analogs (L = PPh/sub 3/, PPh/sub 2/CH/sub 3/ and L/sub 2/ = 2,11-bis(diphenylphosphinomethyl)benzo(c)phenanthrene (TRANSPHOS)) was carried out. The three cis complexes underwent reductive elimination in the presence of coordinating solvents (DMSO, DMF, and THF). The trans complexes which could isomerize to cis (L = PPh/sub 3/, PPh/sub 2/CH/sub 3/) did so in polar solvents and then underwent reductive elimination. TRANSPHOS dimethylpalladium would not undergo reductive elimination of ethane. The eliminations from the cis isomers were intramolecular and displayed first order kinetics. Although TRANSPHOS dimethylpalladium(II) would not undergo a 1,1-reductive elimination of ethane, the addition of CD/sub 3/I to a DMSO solution of this complex at 25/sup 0/C rapidly produced CD/sub 3/-CH/sub 3/, implicating a transient palladium(IV) intermediate. E- and Z-bromostyrylbis(diphenylmethylphosphine)palladium(0) react with methyl lithium in THF at ambient temperature to give the E- and Z- propenylbenzenes, respectively. At -78/sup 0/C, the intermediate E- and Z-styrylmethylbis(diphenylmethylphosphine)palladium(II) complexes (9a,b) can be isolated. On raising the temperature of solutions of 9a,b in THF, E- and Z-propenylbenzenes are produced. The reductive elimination …
Date: September 1, 1980
Creator: Stille, J. K.
Object Type: Report
System: The UNT Digital Library

[Photograph 2012.201.B0352.0001]

Photograph used for a story in the Daily Oklahoman newspaper. Caption: "Koerner, Manager of joint interest operations for the Denver division of Texaco U. S. A. Inc., next month assumes the title of 1994 president-elect of the Society of Petroleum Engineers, a professional group based near Dallas."
Date: September 16, 1993
Creator: Faytinger, David
Object Type: Photograph
System: The Gateway to Oklahoma History
Lead-Zinc-Silver in the Poughkeepsie District and Part of the Upper Uncompahgre and Mineral Point Districts, Ouray and San Juan Counties, Colorado (open access)

Lead-Zinc-Silver in the Poughkeepsie District and Part of the Upper Uncompahgre and Mineral Point Districts, Ouray and San Juan Counties, Colorado

Report issued by the Bureau of Mines over mining districts in Colorado. As noted in the introduction, "in this report the physical features, climate, and ore deposits of the districts are described, and a brief history of mining and production of lead, zinc, and silver is given" (p. 4). This report includes tables, illustrations, and maps.
Date: September 1949
Creator: Hazen, Scott W., Jr.
Object Type: Report
System: The UNT Digital Library

[Photograph 2012.201.B0234.0196]

Photograph taken for a newspaper owned by the Oklahoma Publishing Company.
Date: September 5, 1946
Creator: unknown
Object Type: Photograph
System: The Gateway to Oklahoma History

[Photograph 2012.201.B0230.0436]

Photograph taken for a story in the Daily Oklahoman newspaper. Caption: "The king is dead."
Date: September 21, 1959
Creator: unknown
Object Type: Photograph
System: The Gateway to Oklahoma History

[Photograph 2012.201.B0230.0410]

Photograph taken for a story in the Daily Oklahoman newspaper. Caption: "On his way to an easy victory, Charlie Coe hits an iron shot to second green at Broadmoor."
Date: September 16, 1959
Creator: unknown
Object Type: Photograph
System: The Gateway to Oklahoma History

[Photograph 2012.201.B0234.0194]

Photograph taken for a newspaper owned by the Oklahoma Publishing Company.
Date: September 5, 1946
Creator: unknown
Object Type: Photograph
System: The Gateway to Oklahoma History
Installation Summary - FORT CARSON (open access)

Installation Summary - FORT CARSON

Contains info on location, size, history, missions, major units/tenants, and population.
Date: September 8, 2005
Creator: United States. Department of Defense.
Object Type: Text
System: The UNT Digital Library

[Photograph 2012.201.B0234.0192]

Photograph taken for a newspaper owned by the Oklahoma Publishing Company.
Date: September 5, 1946
Creator: unknown
Object Type: Photograph
System: The Gateway to Oklahoma History

[Photograph 2012.201.B0230.0431]

Photograph taken for a story in the Daily Oklahoman newspaper. Caption: "Charley Coe's long putt takes too much break and just misses the cup on sixth hole of cityan's rain-soaked match with Ted Glechmann of Saticoy, Calif."
Date: September 18, 1959
Creator: unknown
Object Type: Photograph
System: The Gateway to Oklahoma History

[Photograph 2012.201.B0230.0425]

Photograph taken for a story in the Daily Oklahoman newspaper. Caption: "Chipping out of the rough on the 17th hole Friday morning is Oklahoma Cityan Charley Coe en route to a 6 and 4 victory over Dudley Wysong of Dallas in the semifinals of the National Amateur golf tournament at Colorado Springs."
Date: September 19, 1959
Creator: unknown
Object Type: Photograph
System: The Gateway to Oklahoma History
Pueblo CD Installation Familiarization Briefing (10 Feb 04) (open access)

Pueblo CD Installation Familiarization Briefing (10 Feb 04)

DISREGARD RESTRICTION HEADER AND FOOTER - Pueblo CD Installation Familiarization Briefing (10 Feb 04)
Date: September 15, 2005
Creator: United States. Department of Defense.
Object Type: Text
System: The UNT Digital Library
Redstone Installation Familiarization Briefing -19 Feb 2004 (open access)

Redstone Installation Familiarization Briefing -19 Feb 2004

DISREGARD RESTRICTION HEADER AND FOOTER - Redstone Installation Familiarization Briefing -19 Feb 2004
Date: September 15, 2005
Creator: United States. Department of Defense.
Object Type: Text
System: The UNT Digital Library
Installation Summary - PUEBLO CHEMICAL DEPOT (open access)

Installation Summary - PUEBLO CHEMICAL DEPOT

Contains info on location, size, history, missions, major units/tenants, and population.
Date: September 12, 2005
Creator: United States. Department of Defense.
Object Type: Text
System: The UNT Digital Library

[Photograph 2012.201.B0230.0411]

Photograph taken for a story in the Oklahoma Times newspaper. Caption: "Charles R. Coe of Oklahoma City came close but missed on this putt on the first green at the Broadmoor course in Colorado Springs Thursday."
Date: September 18, 1959
Creator: unknown
Object Type: Photograph
System: The Gateway to Oklahoma History

[Photograph 2012.201.B0243.0076]

Photograph taken for a story in the Daily Oklahoman newspaper. Caption: "Vic Couch )extreme right) is one of the few gold miners left in Central City, CO- although tourists do most of the work, paying $1 a day for the thrill of panning at least 20 cents worth of gold from the sediment."
Date: September 7, 1969
Creator: unknown
Object Type: Photograph
System: The Gateway to Oklahoma History
Fort Carson Installation Familiarization Briefing 6 APRIL 04 (open access)

Fort Carson Installation Familiarization Briefing 6 APRIL 04

DISREGARD RESTRICTION HEADER AND FOOTER - Fort Carson Installation Familiarization Briefing 6 APRIL 04
Date: September 14, 2005
Creator: United States. Department of Defense.
Object Type: Text
System: The UNT Digital Library

[Photograph 2012.201.B0234.0197]

Photograph taken for a newspaper owned by the Oklahoma Publishing Company.
Date: September 5, 1946
Creator: unknown
Object Type: Photograph
System: The Gateway to Oklahoma History

[Photograph 2012.201.B0234.0198]

Photograph taken for a newspaper owned by the Oklahoma Publishing Company.
Date: September 5, 1946
Creator: unknown
Object Type: Photograph
System: The Gateway to Oklahoma History
Army Installations and State Action Papers - Colorado (open access)

Army Installations and State Action Papers - Colorado

Disregard Restriction of Header and Footer: Army Installations and State Action Papers - Colorado
Date: September 21, 2005
Creator: United States. Department of Defense.
Object Type: Text
System: The UNT Digital Library
[Letter from Lillian Roberts to Marie Genaro, September 18, 1979] (open access)

[Letter from Lillian Roberts to Marie Genaro, September 18, 1979]

Letter from Lillian Roberts to Marie Genaro expressing displeasure with the Texas Ten's decision to send their petition to the class secretaries in addition to the board of directors.
Date: September 18, 1979
Creator: Roberts, Lillian
Object Type: Letter
System: The Portal to Texas History
[Certificate of Appreciation] (open access)

[Certificate of Appreciation]

Certificate presented to Rigdon "Rig" Edwards at the 1978 WASP Reunion in Colorado Springs, Colorado acknowledging his "wholehearted and dedicated service to the WASP organization."
Date: September 1978
Creator: Women Airforce Service Pilots (U.S.)
Object Type: Text
System: The Portal to Texas History
Mean and Peak Wind Load Reduction on Heliostats (open access)

Mean and Peak Wind Load Reduction on Heliostats

This report presents the results of wind-tunnel tests supported through the Solar Energy Research Institute (SERI) by the Office of Solar Thermal Technology of the US Department of Energy as part of the SERI research effort on innovative concentrators. As gravity loads on drive mechanisms are reduced through stretched-membrane technology, the wind-load contribution of the required drive capacity increases in percentage. Reduction of wind loads can provide economy in support structure and heliostat drive. Wind-tunnel tests have been directed at finding methods to reduce wind loads on heliostats. The tests investigated both mean and peak forces, and moments. A significant increase in ability to predict heliostat wind loads and their reduction within a heliostat field was achieved. In addition, a preliminary review of wind loads on parabolic dish collectors was conducted, resulting in a recommended research program for these type collectors. 42 refs., 38 figs., 1 tab.
Date: September 1, 1987
Creator: Peterka, J. A.; Tan, L.; Bienkiewcz, B. & Cermak, J. E.
Object Type: Report
System: The UNT Digital Library
Palladium Catalyzed Coupling Reactions: Mechanism of Reductive Elimination. Progress Report, June 1, 1978-September 30, 1979 (open access)

Palladium Catalyzed Coupling Reactions: Mechanism of Reductive Elimination. Progress Report, June 1, 1978-September 30, 1979

The coupling reaction of benzyl halides and organolithium, organotin, or Grignard Reagents is catalyzed by palladium. The sequence of events in the catalytic cycle is oxidative addition of the benzyl halide to palladium(0), methathesis by the organometallic reagent to give a benzyl methyl palladium(II) complex, oxidative addition of the benzyl halide to give a palladium(IV) complex, and reductive elimination of benzyl and methyl to give ethylbenzene. The reductive elimination from palladium bearing an optically active ..cap alpha..-deuteriobenzyl group takes place with retention of configuration at carbon, and is therefore concerted or nearly concerted. Since rho is positive in the catalytic reaction with substituted aryl halides, an oxidative addition, probably during the Pd(II) to Pd(IV) reaction, is the slow step in the catalytic cycle. The intermediate diorganopalladium species can be isolated when the two groups attached to palladium are both methyl or methyl and either cis or trans-..beta..-styryl. The decomposition of these species can be followed by NMR. In the case of methylstyrylpalladium(II) complexes, the reductive elimination gives propenyl benzene with stereospecific retention of double bond geometry. Cis-dimethylbis(diphenylmethylphosphine)palladium(II) does not undergo isomerization to the more stable trans isomer in an inert solvent, and is stable toward reductive elimination up to 50/sup …
Date: September 1, 1979
Creator: Stille, J. K.
Object Type: Report
System: The UNT Digital Library