pinacol वाक्य

Pinacol can be used with borane and boron trichloride to produce useful synthetic intermediates such as pinacolborane, bis ( pinacolato ) diboron, and pinacolchloroborane.
While similar to the pinacol rearrangement, the semipinacol rearrangement differs from the pinacol rearrangement in that the cation is not formed from a vicinal 1, 2-diol.
While similar to the pinacol rearrangement, the semipinacol rearrangement differs from the pinacol rearrangement in that the cation is not formed from a vicinal 1, 2-diol.
The diols used to create NanoPilgrim and NanoTexan were made through reductive pinacol coupling of the 1, 4-and 1, 5-diketones with SmI 2 and Mg / TiCl 4.
One example is the chloroalkyllithium carbenoid reagent prepared " in situ " from a sulfoxide and " t "-BuLi which inserts into the carbon-boron bond of a pinacol boronic ester:

This diketone reaction is related to other rearrangements : the corresponding keto-aldehyde ( one alkyl group replaced by hydrogen ) rearranges in a Cannizzaro reaction, the corresponding 1, 2-diol reacts in a pinacol rearrangement.
A related reaction, a Pinacol cascade which produces a tetrahydrofuran, has also been used extensively by the Overman group, for example in the total synthesis of ( )-magellanine, a " Lycopodium " alkaloid.
The Grob fragmentation can be applied as an example of such an expansion . & & Like the pinacol type migration the Grob fragmentation relies on an electron donating group to promote the bond migration and encourage the leaving group to be expelled.
In p-type doping of silicon, a covalently anchored monolayer of allylboronic acid pinacol ester is formed on the surface as the boron precursor while a monolayer of diethyl 1-propylphosphonate is used as the phosphorus precursor in n-type doping.
The A ring closure required two ketone groups for a pinacol coupling which were realized by oxidation of the C11 alcohol ( TPAP, NMO ) to ketone "'36 "'and Wacker oxidation of the allyl group to diketone "'37 " '.