Organic Chemistry flashcards, generated for you.

A chemical bond formed by the sharing of electron pairs between two atoms. The shared electrons are attracted to the nuclei of both atoms, holding them together.

Nucleophile: electron-rich species that donates electrons to form a bond (attracted to positive charge). Electrophile: electron-deficient species that accepts electrons (attracted to negative charge).

Bimolecular nucleophilic substitution. The nucleophile attacks from the backside (opposite the leaving group) in one concerted step, causing inversion of stereochemistry. Rate depends on concentrations of both reactants.

SN1: unimolecular, two-step, involves carbocation intermediate, racemization occurs, rate = k[substrate]. SN2: bimolecular, one-step, backside attack, inversion of stereochemistry, rate = k[substrate][nucleophile].

A positively charged carbon atom with three bonds and an empty p-orbital. Stability increases with substitution (3° > 2° > 1° > methyl) due to hyperconjugation and inductive effects from alkyl groups donating electron density.

In addition reactions to unsymmetrical alkenes, H adds to the carbon with more hydrogens. Occurs because the electrophile (H⁺ or X⁺) adds first to form the more stable carbocation, then the nucleophile attacks that carbocation.

Elimination: removal of a small group and formation of a double bond. E1: unimolecular, two-step, via carbocation, rate = k[substrate]. E2: bimolecular, one-step, concerted, requires strong base, anti-periplanar geometry required.

Step 1: electrophile attacks π-electrons of benzene, forming resonance-stabilized carbocation intermediate (arenium ion). Step 2: deprotonation restores aromaticity and forms substituted benzene. Requires strong electrophile (generated from electrophilic activator).

Directing groups activate/deactivate the benzene ring and direct incoming electrophile. Ortho/para directors (e.g., -OH, -NH₂, -alkyl): donate electron density via resonance, activate ring, direct to ortho/para positions. Meta directors (e.g., -NO₂, -CN, -C≡N): withdraw electrons, deactivate ring, direct to meta position.

A step-by-step description of how bonds break and form during a reaction. Curved arrows show electron pair movement: arrow origin = electron pair source, arrow tip = electron pair destination. Single arrow = one electron pair movement; double-headed arrow shows resonance structures, not electron movement.