Xylyl

Isocyanide is isoelectronic with CO and a reactive compound in the presence of Pd catalysts. The heterobicyclic compound 127 is obtained by the successive insertion of 2.6-xylyl isocyanide (126) into the Pd-hydride bond formed from the hydrosilane[121. Aryl isocyanide inserts into the Si—Si bond in oligo-silanes. For example, 3 mol of 2,6-xylyl isocyanide insert into the tetrasilane 128 to give 129[122],... 

Radicals derived from monocyclic substituted aromatic hydrocarbons and having the free valence at a ring atom (numbered 1) are named phenyl (for benzene as parent, since benzyl is used for the radical C5H5CH2—), cumenyl, mesityl, tolyl, and xylyl. All other radicals are named as substituted phenyl radicals. For radicals having a single free valence in the side chain, these trivial names are retained ... 

Until the 1970s the chemical used as the impregnating and dielectric medium for capacitor units was PCB (polychlorinated biphenyl) liquid. It was found to be toxic and unsafe for humans as well as contamination of the environment. For this reason, it is no longer used. The latest trend is to use a non-PCB, non-toxic, phenyl xylyl ethane (PXE-oil), which is a synthetic dielectric liquid of extremely low loss for insulation and impregnation of the capacitor elements or to use mixed polypropylene or allpolypropylene (PP) liquids as the dielectric. A non-oil dielectric, such as epoxy resin, is also used. 

The ortho-xylyl unit may be considered as the synthetic complement of the catechol unit so often used in crown synthesis. This is especially so for the 1,2-bromomethyl compounds which may be used as electrophiles. These units have been incorporated in numerous crowns over the years and the syntheses are all quite similar. 

The vinyl ehloride derivative [(> -Tp )Rh(CNBu-t)(CH2=CH)Cl] when rea-eted with Cp2ZrH2 gives the vinyl hydride [(j -Tp )Rh(CNBu-t)(CH2=CH)H] (990M495). In CgDg at room temperature, the produet transforms into the ethylene eomplex [(>j -Tp )Rh(CNBu-t)(j7 -CH2=CH2)] by intramoleeular isomerization. A similar eomplex, [(>j -Tp )Rh(CN-2,6-xylyl)(>j -CH2=CH2)], is also known (980M4784,980M5148). Photolysis of [(j -Tp )Rh(CNBu-t)(PhN=C=NBu-t)]... 

Polymer-supported BINOLs thus prepared were treated with Zr(Ot-Bu)4 to form polymer-supported zirconium 20. In the presence of 20 mol% of various zirconium 20, the model aza Diels-Alder reactions of imine Id with Danishefsky s diene (7a) were performed results from selected examples are shown in Table 5.8. Whereas the 4-t-butylphenyl group resulted in lower enantiomeric excess (ee), higher ee were obtained when 3,5-xylyl, 4-biphenyl, 4-fluorophenyl, and 3-tri-... 

There are also, although not much met with, an aldehyde and a cyanide musk. The former is dinitro-tertiary - butyl-xylyl-aldehyde, Cg(CH3),C(CH3)3(NO,),CHO, melting at 112°, and the latter is diniti n-tertiary-butyl-xylyl-cyanide, Cg(CH3),CN. C(CH3)3(N03), melting at 110°. 

Explosion Temperature. 1 Osec at 435 ° (Ref 11) Flammability. The flammability of AP, as measured by the min weight of a primer which will ignite it, was found to lie betw Xylyl (a Russian expl) and TNT (Ref 38)... 

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