2-propynyl

It is used as an intermediate in preparation of the miticide Omite [2312-35-8] 2-(T-/ f2 -butylphenoxy)cyclohexyl 2-propynyl sulfite (40) sulfadiazine [68-35-9] (41) and halogenated propargyl carbonate fungicides (42). 

AIkyl-Ai,A/-diaLkyl-l-naphthalenecarboxamides are useful herbicides (86) and the 2,2-dimeth5lhydra2ide of 1-naphthalenecarboxyhc acid has been patented as a plant growth regulator (87). 2-Propynyl-2-naphthalenecarboxylate [53548-27-9] and similar esters are insecticides (88). 1-Naphthaleneacetic acid, the plant growth regulator, has been prepared from naphthalene, concentrated HCl, and paraformaldehyde without isolation of intermediate 1-chloromethylnaphthalene or l-naphthaleneacetonitnle (89). 

Cinnamyl—sesamol ethers, eg (35), are useful as insect chemosterilants (111). 3,4-Methylenedioxyphenyl-3-halo-2-propynyl ethers (36, X = halogen) are synergists for carbamate insecticides (112). HaloaLkyl or haloalkenyl ethers, eg (37), show acaricidal and insect juvenile hormone activity (113). The first total synthesis of gibbereUic acid was from 2-methoxy-6-aLkoxyethyl-l,4-benzoquinone, a derivative of hydroxyhydroquinone (114). 

Haloprogin. 3-Iodo-2-propynyl 2,4,5-trichlorophenyl ether, is an almost iasoluble antifungal for topical use, available ia the United... 

Acrylic acid, -(3-benzo[f>]thienyl)-a -mercapto-reaction with iodine, 4, 764 Acrylic acid, o -cyano-y3-(2-thienyl)-ring opening, 4, 807 Acrylic acid, -formyl-in pyridazinone synthesis, 3, 46 Acrylic acid, furyl-rotamers, 4, 545 synthesis, 4, 658 Acrylic acid, 2-hydroxybenzoyl-chroman-4-one synthesis from, 3, 850 Acrylic acid, 5-(l-propynyl)-2-thienyl-methyl ester occurrence, 4, 909 Acrylonitrile... 

The reaction of the ethynylestradiol derivative (50) with difluorocarbene represents an equally fascinating series of reactions. The major product obtained in 48% yield is the difluorocyclopropene (51). The latter is hydrolyzed to the cyclopropenone (53), and is readily alkylated at C-21 to (54), which is also obtained by difluoromethylation of the propynyl derivative (57). The cyclopropenone (53) loses carbon monoxide at elevated temperature to... 

The alkynylation of estrone methyl ether with the lithium, sodium and potassium derivatives of propargyl alcohol, 3-butyn-l-ol, and propargyl aldehyde diethyl acetal in pyridine and dioxane has been studied by Miller. Every combination of alkali metal and alkyne tried, but one, gives the 17a-alkylated products (65a), (65c) and (65d). The exception is alkynylation with the potassium derivative of propargyl aldehyde diethyl acetal in pyridine at room temperature, which produces a mixture of epimeric 17-(3, 3 -diethoxy-T-propynyl) derivatives. The rate of alkynylation of estrone methyl ether depends on the structure of the alkyne and proceeds in the order propar-gylaldehyde diethyl acetal > 3-butyn-l-ol > propargyl alcohol. The reactivity of the alkali metal salts is in the order potassium > sodium > lithium. 

With higher homologs e.g., propynyl, butynyl), 3j5-hydroxyandrost-5-en-17-one does not react well with the alkyne and potassium r-butoxide, or with the lithium alkyne in tetrahydrofuran. However, satisfactory results are obtained by use of the alkynylmagnesium bromide in tetrahydrofuran, ... 

Silver trifluoroacetate is a suitable catalyst for various cationic rearrangements involving multiple carbon-carbon bonds [49 5(1] In the presence of silver trifluoroacetate, 2 propynyl acetates rearrange to the butadienyl acetates to give dienes that are useful in Diels-Alder reactions [49] (equation 22)... 

The discovery of junipal focused the attention of Sorensen, who had been investigating the occurrence of polyacetylenes in Com-positae, on the possibility that these acetylenes were accompanied by thiophenes. From Coreopsis grandiflora Hogg ex sweet, 2-phenyl 5-(1-propynyl) thiophene (240) was isolated and its structure confirmed by synthesis of the tetrahydro compound, 2-phenyl-5-n-propyl-thiophene. From the root of tansy, the cis and trans isomers of methyl 5-(l-propynyl)-2-thienylacrylate (241) have been isolated. The total synthesis of trans (241) was achieved by reacting junipal with methylcarbethoxy triphenylphosphonium bromide (Wittig reaction) Several monosubstituted thiophenes, (242), (243), and... 

It is interesting that the cyclization of the 2,4-dinitrophenylhydrazone of the aliphatic analog, l,5-dimethylpentadione-3, can also be performed in alkaline conditions. Heating hydrazine in boiling methanol in the presence of sodium methoxide results in l-(2,4-dinitrophenyl)-3-propynyl-5-methylpyrazole (84%) (74JOC843). 

Similarly, dipropynylketone behaves as an aliphatic analog which forms the corresponding 5-methyl-3-(l-propynyl)pyrazoles (70-90% yield) with hydrazine or monosubstituted hydrazines in methyl alcohol at room temperature (74ZOR136) (Scheme 23). 

Boiled in a water-dioxane solution in the presence of acids, these compounds turn into l-alkyl-3-propynyl-5-methylpyrazoles (Scheme 25). 

The ehloiine atom does not reaet in these eonditions, and 5-ehloro-4-(l -propynyl-... 

---