Answer:
To fulfill octet of B atom in borane, nucleophilic attack by pi electrons of alkene takes place with electrophilic B center in borane.
Explanation:
In Borane (), B atom has energetically vacant 2p orbital and thereby octet is incomplete.Therefore B center in borane act as an electrophilic center.
In alkene, pi bonding electrons are loosely bound together due to side on overlap of two constituent p-orbitals. Hence this pi bond can be easily broken. Alternatively, we can say that pi bond in alkene act as a potential nucleophile.
The first step of hydroboration occurs in a concerted manner where pi electrons of alkene first attack vacant 2p orbital of B in borane to fulfill it's octet (represented by an arrow drawn from alkene to B atom) and forms a 4 memebered cyclic intermediate. Simulaneously, a B-H bond in borane is donated to alkene through 3c-2e bond (3 center-2 electron bond).
Full mechanism has been shown below.
Answer:
it is because a number of factors, including sample surface cleanliness and temperature, can prevent chunks of alkali metals from exploding on contact with water. The team eliminated those variables and others by using a sodium-potassium alloy that remains liquid at room temperature and a droplet delivery system featuring a calibrated syringe.
Answer:
Let x equal the percentage abundance of one of the two isotopes. The other isotope must then have an abundance of 100 percent minus x percent, which you express in decimal form as (1 - x). For nitrogen, you can set x equal to the abundance of N14 and (1 - x) as the abundance of N15.
Explanation:
Answer:
It’s not only about ‘changing light bulbs’ – it’s about changing attitudes and behavior.
Explanation: