Substituted activated methylene reagents and methods of using such reagents to form electron deficient olefins
View Patent ↗This invention relates to substituted activated methylene reagents and methods of using such reagents to form electron deficient olefins such as butadienes.
1. Compounds comprising structure A:
wherein:
wherein X and X′ are each independently an electron withdrawing group selected from CN, CO 2 R, CO 2 H, COCl, COR, COPO(OR) 2 , COPOR 2 , SO 2 R, SO 3 R or NO 2 , where R is C1-4;
L is a leaving group;
W is H, alkyl, cycloaliphatic or aryl; and
R′ is H, alkyl, or a cation selected from the group consisting of alkali metal cations, ammonium cations and phosphonium cations.
2. Compounds comprising structure C:
wherein:
wherein X″ and X″′ are each independently an electron withdrawing group selected from CN, CO 2 R, CO 2 H, COCl, COR, COPO(OR) 2 , COPOR 2 , SO 2 R, SO 3 R or NO 2 , where R is C1-4;
L is a leaving group;
W is H, alkyl, cycloaliphatic or aryl;
R″ is an alkylene with or without substitution or interruption by heteroatom; and
n is 2-4.
3. Compounds of claim 2 , embraced by structure D:
wherein:
wherein X, X′, X″ and X″′ are each independently an electron withdrawing group selected from CN, CO 2 R, CO 2 H, COCl, COR, COPO(OR) 2 , COPOR 2 , SO 2 R, SO 3 R or NO 2 , where R is C1-4;
L is a leaving group;
W is H, alkyl, cycloaliphatic or aryl;
R″ is an alkylene with or without substitution or interruption by heteroatom;
n is 2-4.
4. A method of making compounds of structure C
wherein:
wherein X″ and X″′ are each independently an electron withdrawing group selected from CN, CO 2 R, CO 2 H, COCl, COR, COPO(OR) 2 , COPOR 2 , SO 2 R, SO 3 R or NO 2 , where R is C1-4;
L is a leaving group;
W is H, alkyl, cycloaliphatic or aryl;
R″ is a spacer; and
n is 2-4,
comprising the steps of:
(a) providing compounds of structure I:
wherein:
X and X″ are each independently an electron withdrawing group;
L is a leaving group; and
W is H, alkyl, cycloaliphatic or aryl;
(b) exposing the compounds of structure I to (i) conditions appropriate to form compounds of structure A as defined in claim 1 wherein R′ is H or (ii) conditions appropriate to form compounds of structure C as defined in claim 2 ; and
(c) optionally, exposing the compound formed in step (b)(i) above to conditions appropriate to form compounds of structure C.
5. The method of claim 4 , wherein the conditions of step (c) involve providing R″-(OH) n , wherein R″ is a spacer and n is 2-4 so as to form n functional esters in compounds of structure C.
6. The method of claim 4 , wherein structure I is
7. The method of claim 5 , wherein structure I is
8. The method of claim 4 , wherein structure I is reacted with a basic compound at elevated temperatures to form structure C.
9. The method of claim 4 , wherein when in structure A R′ is H, structure A is esterified under appropriate conditions.
10. The method of claim 8 , wherein the basic compound is a member selected from the group consisting of morpholine, piperidine, pyrrolidine, piperazine, 1,3,3 trimethyl 6-azabicyclo[3,2,1]octane, thiazolidine, homopiperazine, aziridine, 1,4-diazabicylo[2.2.2]octane, 1-amino-4-methylpiperazine, lithium bases, and 3-pyrroline.
11. The method of claim 8 , wherein the elevated temperature conditions are above 100° C.
12. Compounds according to claim 1 , wherein L is selected from the group consisting of halogen, amine, and phosphonate.