US 12,410,149 B2
Substituted chromanes, analogs thereof, and methods of use and synthesis
Karl A. Scheidt, Evanston, IL (US); Rick C. Betori, Gurnee, IL (US); and Benjamin R. McDonald, Somerville, MA (US)
Assigned to Northwestern University, Evanston, IL (US)
Filed by Northwestern University, Evanston, IL (US)
Filed on Mar. 21, 2023, as Appl. No. 18/187,380.
Application 18/187,380 is a division of application No. 16/923,843, filed on Jul. 8, 2020, granted, now 11,639,340.
Claims priority of provisional application 62/871,673, filed on Jul. 8, 2019.
Prior Publication US 2023/0339879 A1, Oct. 26, 2023
Int. Cl. C07D 311/58 (2006.01); C07C 67/303 (2006.01); C07D 215/14 (2006.01); C07D 215/58 (2006.01); C07D 307/80 (2006.01); C07D 311/64 (2006.01); C07D 311/92 (2006.01)
CPC C07D 311/58 (2013.01) [C07C 67/303 (2013.01); C07D 215/14 (2013.01); C07D 215/58 (2013.01); C07D 307/80 (2013.01); C07D 311/64 (2013.01); C07D 311/92 (2013.01)] 17 Claims
 
1. A method of synthesizing a compound of formula,

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or a salt or hydrate thereof,
the method comprising irradiating reagents comprising:
(a) a compound having a formula selected from

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wherein:
R1 and R2 are independently selected from hydrogen, alkyl, alkoxy, carboxy, and carboxyalkyl;
R3 and R4 are independently selected from hydrogen, alkyl, alkoxy, carboxy, carboxyalkyl, aryl, carboxyalkylaryl (e.g., carboxybenzyl ester), and cyano;
Optionally, wherein at least one of R1, R2, R3, and R4, is not hydrogen;
R5, R6, R7, and R8 are independently selected from hydrogen, alkyl, alkoxy, halo and optionally R7 and R8 form an aryl group;
X is selected from oxygen, nitrogen (NH), and carbon (CH2); and
n is an integer selected from 0-1;
(b) a photocatalyst selected from the group consisting of

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(c) a Lewis acid selected from the group consisting of Sc(OTf)3, M(OTf)2, La(OTf)3, and LiCl; and
(d) a reducing agent, wherein the reducing agent is a Hantzsch ester of formula

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 or
N,N-diisopropylethylamine (DIPEA), triethylamine (NEt3), tributylamine 2 (NBu3), or 2-phenyl-dihydrobenzothaizoline (BT).