Reagents List/ Cheat Sheet

HX (HCl, HBr, HI) + alkene → H on one C, X on the MORE substituted C (Markovnikov). Carbocation, so check for rearrangement. No syn/anti.

HBr + ROOR + alkene → H on one C, Br on the LESS substituted C (anti-Markovnikov). Only works with HBr. No syn/anti.

H3O+ (H2O, acid) + alkene → H on one C, OH on the MORE substituted C (Markovnikov). Carbocation, so check for rearrangement. No syn/anti.

1) Hg(OAc)2, H2O 2) NaBH4 + alkene → adds OH (Hg = "oxygen added"). OH on the MORE substituted C (Markovnikov). NO rearrangement. No syn/anti.

1) BH3 2) H2O2, OH- + alkene → adds OH on the LESS substituted C (anti-Markovnikov). SYN: H and OH go on the same face (both wedge or both dash). No rearrangement.

X2 (Br2, Cl2) + alkene → one X on each alkene C. C=C becomes C-C. ANTI: one X wedge, one X dash. No rearrangement.

X2 in H2O (or ROH) + alkene → X on the LESS substituted C, OH (or OR) on the MORE substituted C. ANTI: one wedge, one dash. Halohydrin.

H2, Pt/Pd/Ni + alkene → H on each C, makes alkane. SYN: both H's same face (both wedge).

1) OsO4 2) NaHSO3 + alkene → OH on each C (diol). SYN: both OH's same face (both wedge or both dash).

1) O3 2) Zn or S(CH3)2 + alkene → C=C is CUT in half. Each C becomes C=O. C with an H becomes an aldehyde, C with two R groups becomes a ketone.

1) O3 2) Zn or S(CH3)2 + alkyne → C≡C is cut. Each C becomes a carboxylic acid (COOH).

ALKYNE: H2, Pt/Pd/Ni → goes all the way to alkane (adds 2 H2). Can't stop at the alkene.

ALKYNE: H2, Lindlar → stops at CIS alkene (both H's on the same side, syn).

ALKYNE: Na (or Li), NH3 → stops at TRANS alkene (H's on opposite sides).

ALKYNE: HX (1 equiv) → C≡C becomes C=C. H on one C, X on the more substituted C.

ALKYNE: HX (2 equiv or excess) → C≡C becomes C-C. BOTH X's on the SAME carbon (the more substituted one). Other C gets 2 H's total.

ALKYNE: X2 (1 equiv) → C≡C becomes C=C. One X on each C, trans (anti).

ALKYNE: X2 (2 equiv or excess) → C≡C becomes C-C. Each carbon gets 2 X's = 4 X's total (the first equiv puts 1 X on each C, the second equiv puts 1 more on each C).

ALKYNE: HgSO4, H2O (with H2SO4) → adds O. Makes a KETONE. O ends up on the more substituted C (Markovnikov). Terminal alkyne gives a methyl ketone.

ALKYNE: 1) BH3-type (Sia2BH or 9-BBN) 2) H2O2, OH- → adds O on the LESS substituted C (anti-Markovnikov). Terminal alkyne gives an ALDEHYDE. Internal alkyne gives a ketone.

ALKYNE: HBr + ROOR → anti-Markovnikov. Br on the less substituted C.

1) NaNH2 2) R-X → TERMINAL alkyne only. The end C-H becomes C-R (longer alkyne). R-X must be methyl or primary.

1) X2 2) NaNH2 → makes an ALKYNE from an alkene. X2 adds across C=C, then NaNH2 removes 2 HX (double elimination).

X2, light (hv) → radical substitution on an ALKANE. Replaces an H with X. Br2 picks the most substituted C (3° > 2° > 1°). Not addition.

NBS, hv or ROOR → radical. Puts Br on the ALLYLIC carbon (the C next to C=C). The C=C STAYS.

QUICK RULES: Markovnikov = HX, H3O+, Hg(OAc)2, X2/H2O. Anti-Markovnikov = HBr/ROOR, BH3. Carbocation (HX, H3O+) = check rearrangement. Syn = H2/Pt, OsO4, BH3. Anti = X2, X2/H2O. Lindlar = cis. Na/NH3 = trans. Alkyne + 2 equiv = both pi bonds used up.