DD261360A1 - METHOD FOR PRODUCING METHYLENE BIS- (N-ACYL ISOTHIOROUS SUBSTANCES) - Google Patents

Abstract

The invention relates in the process for the preparation of methylene-bis (N-acyl-isothioureas) of the general formula I in which R is an aryl, optionally substituted on the phenyl nucleus aryl group; Pyrid-2,3,4-yl; N-oxy-pyrid-2,3,4-yl group or benzthiazol-2-yl group and R 1 is an aryl; optionally substituted on the phenyl nucleus one or more times by halogens substituted aryl group. The aim of the invention is to produce methylene bis (N-acyl-isothioureas) in a simple, economically favorable manner. According to the invention, under simple reaction conditions, aryl or hetarylamides are reacted with substituted isothiocyanates and subsequent alkylation with dihaloalkanes to form methylene-bis- (N-acyl-isothioureas). Methylene bis (N-acyl isothioureas) are important intermediates for crop protection agents. Formula I

Description

Fields of application of the invention

The invention relates to a process for the preparation of methylene-bis-fN-acyl-isothioureas) of the general formula I in which R is an aryl, optionally substituted on the phenyl nucleus aryl group; Pyrid-2,3,4-VL; N-oxy-pyrid-2,3,4-yl group or benzthiazol-2-yl group mean. These compounds are important intermediates for the synthesis of crop protection agents.

It is known that some substituted methylene-bis-dithioesterderivate z. B. the methylene-bis-falkali-cyanimidodithioester); Bis (4-amino-thiazole-2-thio) -methanes and others which are fungicidal, insecticidal, bactericidal, useful as pesticides and are potential intermediates for pharmaceuticals and dyes.

Characteristic of the known technical solutions

So far, only substituted methylene-bis-dithioesters are known (see DD-256443; 112887; 147100; 241256; 241 204; 221177 and BRD Patent 3013104) which are obtained by known methods by e.g. Dialkyl cyanimidodithiocarbonate with dihalomethane, such as. For example, chlorobromoethane over methylene bis (Kaliumcyanimidodithiocarbonate (see DD 147100) to methylene-bis (alkylcyanimidodithiocarbonaten) (see this DD-221177) to be implemented.

Further, unsymmetrically substituted methylene bridged dithioesters are obtained by alkylating the cyanimidiodithiocarbonates with CH-acidic components (see, for example, Z. Chem. 20 [1980], 370 and BRD Patent 3013104 [1980]). No methylene bis (N-acyl isothioureas) of the general formula I have been described. This class of substance has hitherto been unknown and not accessible.

Object of the invention

The aim of the invention are methylene-bis-tN-acyl-isothioureas) to produce an economically favorable process.

Explanation of the essence of the invention

The invention is based on the object, methylene-bis-fN-acyl-isothioureas) to produce a simple, economical process.

According to the invention, methylene-bis-fN-acyl-isothioureas) of the general formula (I) _f

R-CO-I = C

\ - GH ₉ -

R ¹ -

C = N - CO - R

in which

R is aryl, het-aryl, optionally phenyl-substituted aryl; Pyrid-2,3,4-yl, N-oxy-pyrid-2,3,4-yl; Benzothiazol-2-yl; stands,

R ^{1 is} aryl, optionally mono- or polysubstituted by halogens at the phenyl nucleus aryl group, is prepared by reacting substituted aryl or Hetarylamiden of the general formula II, in which R has the same meaning as in formula I, with substituted isothiocyanates the general formula III in which R ^{1 has} the same meaning as in formula I, in an inert solvent such. For example, dimethyl sulfoxide or dimethylformamide, in the presence of a base such as sodium hydroxide or sodium hydride, at -20 ° C to 0 ° C and alkylating agents ₍ such as, for example, diiodomethane.

The method according to the invention is illustrated by equation 1.

By the method according to the invention, for example, the compounds of Table 1, page 5 can be produced.

embodiments example 1

Methylene to N- (2-bromobenzoyl) -N'-phenylisothiourea

5 g (0.025 mol) of 2-bromobenzamide are in 50ml abs. Dissolved dimethylformamide and treated at -1O ⁰ C to 2O ⁰ C under nitrogen atmosphere in portions with 1 g (0.04 mol) of sodium hydride. After 30min. Stirring 2.8 g (0.02 mol) of phenyl isothiocyanate dissolved in 20 ml of absolute dimethylformamide are added dropwise and 30 min. stirred at room temperature. Thereafter, at ⁰ ° C., 0.01 mole of diiododomethane in 10 mol of absolute dimethylformamide is added dropwise and the mixture is stirred at room temperature for about 5 hours. The reaction solution is poured into 400 ml of ice water, the solid is filtered off with suction and recrystallized from ethanol.

Example 2

Methylene to N- (pyrid-2-oyl) -N'-phenylisothiourea

2.7 g (0.02 mol) of pyrid-2yl-amide are placed in 50 ml of absolute dimethyl sulfoxide and treated with cooling with 1 g (0.04 mol) of sodium hydride in portions. After stirring for 2 hours, 3 g (0.02 mol) of phenyl isothiocyanate are added dropwise in 20 ml of absolute dimethyl sulfoxide and stirred for 3 hours. With 0.01 mol of diiodomethane is aikyliert in OX and stirred after stirring for 3 hours in 200 ml of ice water. Crystalline product is filtered off and recrystallized from ethanol.

Example 3

Methylene to N- (1-oxy-pyrid-3-oyl)

-N'-phenyl-isothiourea

2.6 g (0.02 mol) of N-oxy-pyrid-3-ylamide were added in 50 ml of absolute dimethylformamide at -20 ⁰ C under nitrogen in portions with 1.2 g (0.045 mol) of sodium hydride. After stirring for 1 hour, 3.3 g (0.025 mol) of phenyl isothiocyanate are added dropwise and after 30 min. Stirring at 0 ⁰ C 0.01 mol dibromomethane dissolved in 10 ml of absolute dimethylformamide added. Stirring for 4 hours is poured onto 400 ml of ice water and the resulting solid product is filtered off with suction and purified with ethanol.

Table 1

R R ' Fp ⁰ C Pyrid-3-yl C ₆ H ₅ 176-78 1-oxy-pyrid-3-yl _C6 H5 210-11 Benzothiazol-2-yl C ₆ H ₅ - 188-90 Pyrid-4-yl C ₆ H ₅ 202-04 1-oxy-pyrid-4-yl C ₆ Hs 235-38 Pyrid-2-yl C ₆ H ₅ 101-04 1-oxy-pyrid-2-yl C ₆ H ₅ 178-80 2-bromophenyl C ₆ H ₆ 120-25 2-chlorophenyl C ₆ H ₅ 117-20

Claims (1)

A process for the preparation of methylene-bis-iN-acyl-isothioureas of the general formula I in which R is an aryl group, optionally mono- or polysubstituted by halogens on the phenyl nucleus and substituted aryl group; Pyrid-2,3,4-yl; N-oxy-pyrid-2,3,4-yl group, or benzothiazole ^ -yl group is, wherein R ^{1 is} an aryl, optionally substituted on the phenyl nucleus or polysubstituted by halogens aryl group, characterized in that substituted Aryl or Hetarylamide of the general formula II in which R has the same meaning as in formula I, with substituted isothiocyanates of the general formula III, in the R ^{1 have} the same meaning as in the forms! I, in an inert solvent in the presence of a base such. B. sodium hydride at -20 ⁰ C to 0 ⁰ C and alkylated with diiodomethane. For this 1 page formulas