ch 20/21/22 reagents

H2, Pb/C

Removes any sigma bonds unless poisoned

triple → double → single

NaCCH3

Adds to C=O

X-CN

CN adds to C=O

CN replaces Br/halide

Chromic acid (H2CrO4)

primary alcohol → CBA

secondary alcohol → ketone

aldehyde → CBA

Better, but dangerous

PCC

primary alcohol → aldehyde

secondary alcohol → ketone

KMnO4

primary alcohol → CBA

secondary alcohol → ketone

alkenes → adds alcohol to both sides of bond (no more alkene)

CuI

Makes lithium dialkylcuprate (CuLi-X2) from an alkyllithium reagent (GILMAN REAGENT FORMATION)

ADDS TWO Li MOLECULES TOGETHER

mCPBA

double bond → epoxide (stereospecific)

X-MgBr

Adds -X to least substituted carbon

Grubbs Catalyst

double bonds become one double bond

Ring closing

H2

ketone → alcohol (adds two H)

ZnHg, HCl (H2O)

Removes carbonyl to just 2H

HSCH2CH2SH, H+ (Raney Ni H2)

Removes carbonyl to just 2H

Mg(s), ether

Makes grignard reagent (MgX)

Li(s), ether

Makes alkyllithium reagent (x→Li)

BH3, THF

Adds -OH anti-markovnikov (less substituded C)

H2, Raney Ni

aldehyde → primary alcohol

ketone → secondary alcohol

chloride → primary alcohol

nitrile (CtripleN) → primary amine (-NH2)

PBr3

alcohol → bromide (replaces -OH with -Br)

CO2, H3O+

carboxylation (creates CBA)

LAH

CBA → primary alcohol

acid chloride (C=O C-Cl) → primary alcohol

ester → primary alcohol

amide → amine with no C=O

Protonates cyanide to NH2 (CtripleN → C-NH2)

LDA

Moves carbonyl = to nearby carbon

NaOH

Adds to carbonyl C, kicking off LG if present

Can be saponification

n-BuBr

Adds n-Bu to other side of =

R-B(OR)2

R adds to halogen (R-X → R-R’)

R must be vinylic or aromatic

Uses Pd as a catalyst

SUSKI COUPLING - retains configuration

Pd(OAc)2, PPh3, NEt3

Heck coupling

PPh3X

X adds to carbonyl C

Umpoulung

NaH, CH3I

Williamson ether synthesis

-OH to -O-Ch3 or other

HOCH2CH3OH

Good protecting group for aldehydes

Prevents grignard reagents (X-MgBr) from reacting with itself if an aldehyde is present in the molecule

Intermediate is big pentane group with 2O

NaH, ClCH3OCH3 (MOM-Cl)

Good protecting group for alcohols

Intermediate is alcohol → ether

Hydropyran, H2SO4

Good protecting group for alcohols

Si-C(CH3)3 (TBS-Cl)

Good protecting group for alcohol

Intermediate is a cyclic silyl ether (TBAF)

Acetone, H2SO4

Good protecting group for diols (specifically two 1,3 alcohols)

KO-X

X adds to carbonyl C and kicks off ether

NaOCH3

-OCH3 replaces a halogen (kicks off good leaving group)

Stability Ladder (Best - worst leaving groups)

NH2 (amine) > OH (alcohol) / OR (ether) > CBA > Cl (halogen)

NH2NH2, KOH, heat

Wolff-Kischner reduction

Removes carbonyl entirely

phthalimide + 1) KOH/EtOH 2) R-X 3)KOH, H2O

Gabriel Synthesis - uses amine part

Creates a primary amine

1) Br2, NaOH, H2O 2) HCl, NaHSO3

ketone → CBA

breaks C-CBr3 bond, unusual

Haloform - requires 3 H to replace with 3 Br to make a good LG

NaBH4, EtOH

ketone & halogen → alcohol (kicks off halogen)

NO RXN WITH CBA

LiAlH(OtBu)3

acid chloride → aldehyde

DIBAl-H, HCl, H2O

ester → aldehyde