Dearomatizing Anionic Cyclization and Novel Skeletal Rearrangement:  High Yield Formation of Multiply Substituted Bicyclic or Polycyclic Spirocyclopentadienes and Phenanthrene Derivatives from 4-Aryl 1-Lithio-1,3-butadienes

2007 ◽  
Vol 72 (9) ◽  
pp. 3484-3491 ◽  
Author(s):  
Lantao Liu ◽  
Zhihui Wang ◽  
Fei Zhao ◽  
Zhenfeng Xi
Keyword(s):  
High Yield ◽  
Skeletal Rearrangement ◽  
Yield Formation

Ten-Vertex Polyhedral Monocarbaborane Chemistry. The Novel High-Yield Formation of the Ten-Vertex closo Compound [6-(PMe2Ph)-closo-1-CB9H9] from the Thermolysis of [8,8-(PMe2Ph)2-nido-8,7-PtCB9H11]

1993 ◽  
Vol 58 (12) ◽  
pp. 2924-2935 ◽  
Author(s):  
Jane H. Jones ◽  
Bohumil Štíbr ◽  
John D. Kennedy ◽  
Mark Thornton-Pett
Keyword(s):  
Nmr Spectroscopy ◽  
Diffraction Analysis ◽  
High Yield ◽  
Monoclinic Space Group ◽  
The Novel ◽  
X Ray Diffraction ◽  
Metal Centre ◽  
X Ray ◽  
Yield Formation ◽  
Boiling Toluene

Thermolysis of [8,8-(PMe2Ph)2-nido-8,7-PtCB9H11] in boiling toluene solution results in an elimination of the platinum centre and cluster closure to give the ten-vertex closo species [6-(PMe2Ph)-closo-1-CB9H9] in 85% yield as a colourles air stable solid. The product is characterized by NMR spectroscopy and single-crystal X-ray diffraction analysis. Crystals (from hexane-dichloromethane) are monoclinic, space group P21/c, with a = 903.20(9), b = 1 481.86(11), c = 2 320.0(2) pm, β = 97.860(7)° and Z = 8, and the structure has been refined to R(Rw) = 0.045(0.051) for 3 281 observed reflections with Fo > 2.0σ(Fo). The clean high-yield elimination of a metal centre from a polyhedral metallaborane or metallaheteroborane species is very rare.

scholarly journals Photosynthetic activity of selected genotypes of hops (Humulus lupulus L.) in critical periods for yield formation

2011 ◽  
Vol 57 (No. 6) ◽  
pp. 264-270 ◽  
Author(s):  
J. Pokorný ◽  
J. Pulkrábek ◽  
P. Štranc ◽  
D. Bečka
Keyword(s):  
Photosynthetic Activity ◽  
Photosynthesis Rate ◽  
High Yield ◽  
Critical Periods ◽  
Maturity Level ◽  
Flowering Stage ◽  
Humulus Lupulus L ◽  
Similar Chemical ◽  
New Varieties ◽  
Yield Formation

This paper evaluates the influence of genotype on the photosynthetic activity of hops in the period critical for generating yield. Results over three years from measuring the photosynthesis rate statistically show an increase in the photosynthetic activity of hop plants in the flowering stage. The average photosynthetic rates from measurements on the second date (BBA 65) in the years 2007, 2008, and 2009 increased by 17.9%, 45.6%, and 49.2%, respectively. Different photosynthesis curve trends during the final stage of ontogenesis of the plants indicate the maturity level of each hop genotype. As regards the genotypes for which photosynthesis did not reduce significantly, it may be assumed that such plants had not reached technical maturity. The results from the three-year study also show that any promising genotype, with respect to the photosynthesis rate and yield, is the result of breeding of new varieties with greater resistance to drought and high temperatures. Very good results in photosynthetic activity were reached by the new varieties exhibiting high yield and a similar chemical composition to Saaz hop and those sharing the same origins to Saaz, showing a higher content of bitter substances. In 2008 and 2009, all three new forms reached yield levels of 2.35 to 3.12 t/ha of dry hops.

HIGH-YIELD FORMATION OF ALLYLIC GERMANES BY Pd2(dba)3-CATALYZED REACTION OF ALLYLIC HALIDES WITH DIGERMANES

2001 ◽  
Vol 24 (2) ◽  
Author(s):  
Taichi Nakano ◽  
Sigeyuki Nöda ◽  
Nao-aki A-ihara ◽  
Hirohide Yamashita ◽  
Takashi Miyamoto ◽  
...  
Keyword(s):  
High Yield ◽  
Yield Formation ◽  
Allylic Halides

Design of low-charge peptide sequences for high-yield formation of titaniananoparticles

RSC Advances ◽  
2012 ◽  
Vol 2 (4) ◽  
pp. 1292-1295 ◽  
Author(s):  
Chun-Xia Zhao ◽  
Lei Yu ◽  
Anton P. J. Middelberg
Keyword(s):  
High Yield ◽  
Low Charge ◽  
Yield Formation

Synthesis of Triferrocenylbenzenes by Tantalum(V)-Catalyzed Cyclotrimerization of Ethynylferrocene. The Crystal Structure of 1,3,5-Triferrocenylbenzene

1997 ◽  
Vol 62 (10) ◽  
pp. 1577-1584 ◽  
Author(s):  
Petr Štěpnička ◽  
Ivana Císařová ◽  
Jan Sedláček ◽  
Jiří Vohlídal ◽  
Miroslav Polášek
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Single Crystal ◽  
High Yield ◽  
Isomer Mixture ◽  
State Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Yield Formation

Exclusive, high-yield formation of the cyclotrimers of ethynylferrocene (1) was observed when TaCl5 in benzene was employed as catalyst. Analysis of the resulting isomer mixture by means of HPLC and 1H NMR revealed the presence of 1,3,5-triferrocenylbenzene (sym-2) and 1,2,4-triferrocenylbenzene (asym-2) in the ratio of 4 : 6. A small amount of pure sym-2 isomer was isolated, and its solid-state structure was established by single-crystal X-ray diffraction. The molecules of sym-2 possess a distorted up-up-down arrangement of the ferrocenyl groups attached to the benzene ring.

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