Dithiophosphate derivatives as hydrogen sulfide release chemicals for improving plant growth and crop yield

Abstract

The invention provides a compound of formula (I): wherein X, Y Z, R 1 , R 2 , and X + have any of the values described in the specification. The compounds are useful to increase plant growth and/or to increase harvest yield.

1 . A method comprising, increasing growth or harvest yield by providing H 2 S to a plant or a seed through degradation of a compound of formula I; 
       
         
           
           
               
               
           
         
         wherein:
 Y is O or S; 
 Z is O or S; 
 R 1  is (C 1 -C 20 )alkyl, phenyl, or (C 3 -C 20 )cycloalkyl; and R 2  is (C 1 -C 20 )alkyl, phenyl, or (C 3 -C 20 )cycloalkyl; or R 1  and R 2  taken together with the atoms to which they are attached form a 5-15 membered heterocyclic ring that is optionally substituted with one or more groups independently selected from the group consisting of (C 1 -C 6 )alkyl, (C 3 -C 6 )cycloalkyl, and phenyl, wherein any phenyl or cycloalkyl of R 1  and R 2  is optionally substituted with one or more groups independently selected from the group consisting of (C 1 -C 6 )alkyl, (C 3 -C 6 )cycloalkyl, and phenyl; and 
 X +  is a suitable cation. 
 
       
     
     
         2 . The method of  claim 1 , wherein the growth or the harvest yield is increased by, contacting the plant with the compound of formula I. 
     
     
         3 . The method of  claim 1 , wherein the growth or the harvest yield for a plant that grows from a seed is increased by contacting the seed with a compound as described in  claim 1 . 
     
     
         4 . The method of  claim 3 , wherein the seed is contacted with the compound prior to planting. 
     
     
         5 . The method of  claim 1 , wherein the growth or the harvest yield of the plant is increased by allowing the compound of formula I to degrade on or near the plant, or on or near a seed of the plant, so that H 2 S is provided to the plant or to the seed. 
     
     
         6 - 10 . (canceled) 
     
     
         11 . The method of  claim 1 , wherein the compound releases H 2 S over a period of at least about 2 days after contacting or applying. 
     
     
         12 . (canceled) 
     
     
         13 . The method of  claim 1 , wherein the compound releases H 2 S over a period of at least about 1 year after contacting or applying. 
     
     
         14 - 22 . (canceled) 
     
     
         23 . The method of  claim 1 , wherein R 1  is (C 5 -C 15 )alkyl. 
     
     
         24 . The method of  claim 1 , wherein R 1  is (C 5 -C 10 )alkyl. 
     
     
         25 . (canceled) 
     
     
         26 . The method of  claim 1 , wherein R 1  is phenyl that is optionally substituted with one or more groups independently selected from the group consisting of (C 1 -C 6 )alkyl, (C 3 -C 6 )cycloalkyl, and phenyl. 
     
     
         27 . (canceled) 
     
     
         28 . The method of  claim 1 , wherein R 1  is (C 3 -C 15 )cycloalkyl. 
     
     
         29 - 38 . (canceled) 
     
     
         39 . The method of claim  10 , wherein R 2  is phenyl that is optionally substituted with one or more groups independently selected from the group consisting of (C 1 -C 6 )alkyl, (C 3 -C 6 )cycloalkyl, and phenyl. 
     
     
         40 . (canceled) 
     
     
         41 . The method of  claim 11 , wherein R 2  is (C 3 -C 15 )cycloalkyl. 
     
     
         42 - 50 . (canceled) 
     
     
         51 . The method of  claim 1 , wherein R 1  is selected from the group consisting of: methyl, ethyl, propyl, isopropyl, butyl, iso-butyl, sec-butyl, pentyl, iso-pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, icosanyl, phenyl, 4-ethylphenyl, 
       
         
           
           
               
               
           
         
       
     
     
         52 . The method of  claim 51 , wherein R 2  is selected from the group consisting of: methyl, ethyl, propyl, isopropyl, butyl, iso-butyl, sec-butyl, pentyl, iso-pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, icosanyl, phenyl, 4-ethylphenyl, 
       
         
           
           
               
               
           
         
       
     
     
         53 . The method of  claim 1 , wherein the compound is selected from the group consisting of: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         wherein X +  is a suitable cation. 
       
     
     
         54 . The method of  claim 1 , wherein the compound is: 
       
         
           
           
               
               
           
         
         wherein X +  is a suitable cation. 
       
     
     
         55 - 56 . (canceled) 
     
     
         57 . The method of  claim 1 , wherein X +  is an ammonium cation. 
     
     
         58 . The method of  claim 1 , wherein X +  is potassium, sodium, or triethyl ammonium. 
     
     
         59 . (canceled) 
     
     
         60 . A composition comprising a compound of formula I; 
       
         
           
           
               
               
           
         
         wherein:
 Y is O or S; 
 Z is O or S; 
 R 1  is (C 1 -C 20 )alkyl, phenyl, or (C 3 -C 20 )cycloalkyl; and R 2  is (C 1 -C 20 )alkyl, phenyl, or (C 3 -C 20 )cycloalkyl; or R 1  and R 2  taken together with the atoms to which they are attached form a 5-15 membered heterocyclic ring that is optionally substituted with one or more groups independently selected from the group consisting of (C 1 -C 6 )alkyl, (C 3 -C 6 )cycloalkyl, and phenyl, wherein any phenyl or cycloalkyl of R 1  and R 2  is optionally substituted with one or more groups independently selected from the group consisting of (C 1 -C 6 )alkyl, (C 3 -C 6 )cycloalkyl, and phenyl; and 
 X +  is a suitable cation; 
 
         and a suitable agricultural carrier. 
       
     
     
         61 - 62 . (canceled) 
     
     
         63 . A compound of formula (I). 
       
         
           
           
               
               
           
         
         wherein:
 Y is O or S; 
 Z is O or S; 
 R 1  is (C 1 -C 20 )alkyl, phenyl, or (C 3 -C 20 )cycloalkyl; and R 2  is (C 1 -C 20 )alkyl, phenyl, or (C 3 -C 20 )cycloalkyl; or R 1  and R 2  taken together with the atoms to which they are attached form a 5-15 membered heterocyclic ring that is optionally substituted with one or more groups independently selected from the group consisting of (C 1 -C 6 )alkyl, (C 3 -C 6 )cycloalkyl, and phenyl, wherein any phenyl or cycloalkyl of R 1  and R 2  is optionally substituted with one or more groups independently selected from the group consisting of (C 1 -C 6 )alkyl, (C 3 -C 6 )cycloalkyl, and phenyl, and 
 X +  is a suitable cation. 
 
       
     
     
         64 - 68 . (canceled)