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Cyanohydrin Further Reactions (and their mechanisms):

Cyanohydrins reacting with hydrides produce primary amines.

Basic hydrolysis (usually with an acid, base and water) produces a carboxylic acid an NH3 gas or ammonium salt.

#chemistry #cyanohydrin #organic

Wave Function

How to find the wave function:

Determine the potential energy of the particle.

Apply Schrodinger's equation (usually time-independent).

Plug in the general solution in the formula and solve for k.

Apply boundaries.

Normalize!

The wave function determines a particle's:

position

linear momentum

kinetic energy

potential energy

angular momentum

total energy

#physics #wave function

a-b-s-u-r-d-deactivated20121125

#optics #physics

Gabriel Synthesis

This reaction transforms a primary alkyl halide to a primary amine by using potassium phthalimide, followed by NH2NH2.

In order to form secondary amines, an alternative Gabriel reagent must be used like saccharin since that saccharin can hydrolyze more readily.

#chemistry #gabriel synthesis #mechanism

The Friedal-Crafts Reaction (Alkylation, Acylation through EAS)

The Friedal-Crafts reactions are a set of reactions used to attach groups to an aromatic ring. Alkylation and acylation can be successfully done through electrophilic aromatic substitution, paying close attention to electron donating and withdrawing groups.

In alkylation, the product will be more nucleophilic than the reactant due to addition of electron donating groups (alkyl groups) thus multiple alkylations may occur. (Why is alkyl an electron donating group? Click here to see a previous post about alkyl groups.)

On the other hand, acylation will not occur multiple times because the product is less reactive than the reactants due to the addition of an electron withdrawing group (an acyl group).

* If the chlorine is not on a tertiary carbon, there is a possibility it will rearrange to form a more stable carbocation.

#electrophilic aromatic substitution #alkylation #acylation #friedal-crafts #chemistry

The Greek Alphabet

Let's go back to the basics since the Greek alphabet is most commonly used for technical symbols and labels in many domains in mathematics and sciences.

#greek alphabet #back to the basics

Schrödinger Equation

The Schrödinger equation describes how a quantum state of a physical system changes over time, like propagating a wave function over time.

* Shows how the time-independent (left hand side) and the time-dependent (right hand side) Schrödinger equation was derived.

#physics #quantum #schrodinger equation #waves

Black Holes

"A black hole is a region of spacetime where gravity prevents anything, including light, from escaping.[1] The theory of general relativity predicts that a sufficiently compact mass will deform spacetime to form a black hole. Around a black hole there is a mathematically defined surface called an event horizon that marks the point of no return. It is called "black" because it absorbs all the light that hits the horizon, reflecting nothing, just like a perfect black body in thermodynamics.[2][3] Quantum mechanics predicts that black holes emit radiation like a black body with a finite temperature. This temperature is inversely proportional to the mass of the black hole, making it difficult to observe this radiation for black holes of stellar mass or greater."

#physics #quantum #blackhole #spacetime

Carboxylic Acid Reactions

Carboxylic Acid + SOCl2 or PBr3 = Acyl Halide (With X = Cl or Br)

Carboxylic Acid + Acyl Halide = Acid Anhydride

Carboxylic Acid + Alcohol = Ester

Carboxylic Acid + Amine = Amide (Carbamide)

* Keep in mind that these can also undergo intramolecular reactions and may form cyclic products. Five or six membered rings are thermodynamically favored due to less ring strain.

#carboxylic acid reactions #chemistry

Why is alkyl an electron donating group?

"An alkyl group is a monovalent group. When it is linked to some other group or part of some other molecule it has a tendency to donate electrons. Thus, it is an electron donating group.

In an alkyl group, for example, a methyl carbon is linked to three hydrogen atoms. Carbon is more electronegative than hydrogen. So carbon pulls bonded electrons nearer to carbon, and carbon acquires a slight negative charge (delta-) and correspondingly, hydrogen loses some attraction with bonded electrons and acquires a slight positive charge (delta+). Thus carbon get a little more electronic charge which the carbon will push towards the group to which it is linked.

Thus a methyl group will be electron releasing or electron donating in nature. In an ethyl group (CH3-CH2-) this effect will be more than methyl. The CH3 part releases elecrons to the next carbon plus two hydrogens also make contributions. The net electron releasing effect of ethyl group is more than that of a methyl group."

#chemistry

pKa Values (for ranking questions..)

#chemistry #ranking question #pka

Aldol (Aldehyde + Alcohol) Condensation

An aldol condensation is an organic reaction where an enol or an enolate ion (deprotonated by a base) attacks a carbonyl compound to form a β-hydroxyaldehyde or β-hydroxyketone which is then followed by a dehydration (loss of water) to form an enone (a functional group consisting of an ketone and an alkene).

This reaction forms a new carbon-carbon bond.

#chemistry #organic chemistry #aldol condensation

On All-Nighters..

"Though it is possible to die from lack of sleep, it is highly unlikely that anybody's body will allow them to get to that point. It varies from one person to the next, but the average human will/can experience fatigue, nausea, restlessness, and lightheadedness after 48 hours of no sleep. By the 72 hour mark, those symptoms can build up to audial, visual, and other basic sensory hallucinations. Though after roughly 96 hours of uninterrupted consciousness, the body will usually shut itself down, as a defense mechanism, or will begin to experience bouts of unconsciousness. Whereas most people will fall asleep and stay asleep after 96 hours of no sleep, some people may fall asleep for a matter of moments and do this off and on until the body is recharged enough to stay awake for more than 5 minutes or so. The heart, brain, and lungs all are run by the medula oblongata, and without sleep, this part of the brain will "reset" the whole body to assess how much actual recuperative sleep is needed to maintain involuntary functions."

#advice #studying #all nighter #finals week

The Hofmann Rearrangement

This reaction transforms the primary amide into an intermediate isocyanate. The intermediate isocyanate is hydrolyzed to a primary amine, giving off carbon dioxide.

#chemistry #organic chemistry #hofmann rearrangement