Important things to remember for Orgo 1 final

(Alkynes) → NaNH2 then alkyl halides

other alkynes

(alkynes)→ H2 catalyzed

alkanes

(alkynes) → Hg 2+ catalyzed hydration

ketones R(C=O) R

(Alkynes) → Hydroboration - Oxidation

aldehydes R(C=O)H

(Alkynes) → Na in liquid ammonia

trans alkenes

(Alkynes) → H2, poisoned catalyst

cis alkenes

(Alkenes) → Halogens & water

Halohydrins

(Alkenes) → Simmons Smiths Reaction

Cyclopropanes

(Alkenes) → H2 catalyzed

Alkanes

(Alkenes) → Oxymercuration- Reduction or Hydroboration- Oxidation or Hydration

Alcohols

(Alkenes) → Ozonolysis then Me2S

Aldehydes or Ketones

Ozonolysis then H2O2

Carboxylic Acids R(C=O)OH

Williamson Ether Synthesis

• works best with primary alkyl halides

• an alkoxide attacks an alkyl halide in an SN2 reaction

Alkoxymercuration- Reduction

• uses ROH instead of water as the solvent

• gives Markovnikov(adds on more substituted carbon) addition to ether

Alcohol Dehydration

• secondary and tertiary alcohols form alkenes

• 2 primary alcohols + H2SO4 + heat →symmetrical ether

Percarboxylic Acid (mCPBA)

• stereospecific, concerted syn addition

• adds to both carbons from the same face simultaneously

• cis- alkene = cis - (meso) epoxide

• trans- alkene = trans (racemic) epoxide

Halohydrin Cyclization

• undergoes intramolecular Williamson Ether Synthesis

• OH and X on adjacent carbons treated with base

• SN2 inversion

Epoxide ring opening(under acidic conditions)

• epoxide gets substituted first, nucleophile attacks the most substituted carbon

• inversion at the attacked carbon

• mono-substituted = SN2

Epoxide ring opening (under basic conditions)

• SN2

• nucleophile attacks the less-substituted carbon

• inversion of configuration at the attacked carbon

Oxidation of an alkene to form a glycol

• oxidizing agent : Os(VIII)

• H2O and NaHSO3 (or another reducing agent)

• concerted cycloaddition of OsO4 and alkene

• occurs with syn addition

Oxidation with KMnO4

• H2O, -OH(reagent and solvent)

• under aqueous alkaline conditions

• also forms Manganese (IV) dioxide as precipitate

Oxidative Cleavage (of glycol) with H5IO6

• C-C bond between -OH group is cleaved with the periodic acid

• forms aldehyde and/or ketone

Grignards Reagents (RMgBr)

• attacks less substituted carbon

• extends carbon chain by 2

• gives alcohol

Organocuprates (R2CuLi)

• SN2

• also attacks less substituted carbon

• fewer side reactions