Methyl iodide → HCID 18649291, compound

HRID 1681811Notes

Reaction equation

[OH:1][CH:2]([C@@H:4]1[C@:21]2([CH3:22])[C@H:7]([C@H:8]3[C@H:18]([CH2:19][CH2:20]2)[C@:16]2([CH3:17])[C:11](=[CH:12][C:13](=[O:23])[CH2:14][CH2:15]2)[CH2:10][CH2:9]3)[CH2:6][CH2:5]1)[CH3:3].[CH3:24]C(C)([O-])C.[K+].CI>>[CH3:24][C:12]1[C:13](=[O:23])[CH2:14][CH2:15][C@@:16]2([CH3:17])[C:11]=1[CH2:10][CH2:9][C@@H:8]1[C@@H:18]2[CH2:19][CH2:20][C@@:21]2([CH3:22])[C@H:7]1[CH2:6][CH2:5][C@@H:4]2[CH:2]([OH:1])[CH3:3]

Participants

Reactant 3

HCID 6328Methyl iodide

HCID 16110920-Hydroxypregn-4-en-3-one

HCID 23665647Potassium tert-butoxide

Product 1

HCID 18649291HCID 18649291, compound

Procedure

With reference to Scheme 4, alkylation of 1a, such as 20-hydroxy-4-pregnen-3-one, using potassium t-butoxide and methyl iodide yields 4-methyl-20-hydroxy-4-pregnen-3-one 1b. Allylic bromination of N-bromosuccinimide in carbon tetrachloride yields the 6β-bromo derivative. Protection of the C-20 alcohol as its t-butyldimethyl silyl derivative yields 3. Lithium aluminum hydride reduction of the ketone in 3 with concomitant double bond migration and loss of bromide should yield 4. Protection of the C-3 alcohol as a tetrahydropyranyl ether, followed by deprotection and oxidation of the C-17 alcohol should yield the C-17 ketone 7. Removal of the C-3 tetrahydropyranyl ether yields 4α-methyl-5-pregnen-20-one.

Sources & evidence

ORD record: ord-9b45d2d3f4ca46b386b422aa3446df13
Source dataset: uspto-grants-1992_12
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05175154

Reaction notes

Loading…