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Reactive organozincs obtained from allylic and propargylic bromides regioselectively react with the N -trimethylsilylaldimines prepared in situ from the corresponding carbamates of various α-acetylenic γ-aminoaldehydes to form a new amine function. Thus, we have achieved α-acetylenic primary 1,4-diamines: H 2 N–CH(R′)–CC–CH(R)–NH 2 (R≠R′ or R=R′), then α-ethylenic primary 1,4-diamines ( E ) or ( Z ) through a partial hydrogenation.

Reactive organozincs obtained from allylic and propargylic bromides regioselectively react with the N -trimethylsilylaldimine prepared in situ from the diethylmonoacetal of acetylenedicarbaldehyde and lead to unsatured γ -functional primary amines which possess many synthetic uses.

The reaction between Grignard reagents prepared from allylic or propargylic halides and the N-phenylsulfenimine derived from the heptane-2,6-dione affords primary 1-alkenyl (or alkynyl)-3-methylcyclohex-2-enamines in good yields.

We describe a convenient pathway to prepare primary benzylic diamines with allylic or propargylic groups in α- and α′-positions, by use of the regiospecific reaction between organometallics (M = Zn, Al, Mg) prepared from allylic or propargylic bromides and the bis-N-trimethylsilylimines resulting from an aromatic 1,3- or 1,4-dialdehyde.

Reaction of N-unsubstituted ketimines with organoaluminum reagents prepared from allylic and propargylic halides, allows to prepare, in good yields, tertiary carbinamines with three different groups (phenyl, alkyl and α-unsaturated group) on the tertiary carbon center.

Synthesis of (3-Aminopropyl)arylsilanes, Including One or Two Heterocyclic Patterns, Potential Fungicides Flusilazole is an effective silylated fungicide used on a large scale for plant protection. We synthesized several flusilazole analogs and also copied the tebuconazole design, an other very efficient fungicide, which has four atoms between the aromatic group and the heterocyclic moiety. In contrast to flusilazole, we obtained dissymetric structures around the Si-atom by using successively two different Grignard reagents. In another way, the 1H-1,2,4-triazole moiety was exchanged in several cases by other N-heterocycles such as 1H-imidazole, piperidine, and 2,6-dimethylmorpholine, already present in other fungicidal compounds. Finally, several compounds having two N-heterocycles of the same or different nature were prepared.

A new general synthesis of C-subtituted α -aminoacids is described, using at first the regioselective reaction between α -unsaturated organozincs and N -(phenylsulfanyl)iminoesters.

The α-trimethylsilyl conjugated carbonyl derivatives 1 easily react with organometallics 2 (M = Al, Mg, Zn) and allow preparation of functional vinylsilanes 3 or 4 , in regioselective manner: R'-CH C(SiMe 3 )-C(OH)(R')(R) 3 ; (R')(R)CH-C(SiMe 3 )C(R')(OSiMe 3 ) 4 .

1,1-Bis(trimethylsilyl)-2-propyne, prepared from propargyltrimethylsilane, was reacted, in the presence of a Lewis acid, with electrophiles (aldehydes, acetals) to afford (E)-silylated conjugated enynes.

O-silylated α-aminoesters, resulting from the regioselective reaction between organozinc derivatives and α-iminoesters bearing an alcohol group, are transformed into 3-amino-1,5 (or 1,6)-diols; then 2-allylic-3-amino-1,5-diols are converted into 3-prop-1-enylmorpholines or into 5-s-butyl-2,3-dihydro-6 H -1,4-oxazines.

The one-pot synthesis of 2-cyano-4-N,N-dimethylaminobut-2-en-1-ols is easily obtained by using allylic lithioanion prepared from 4-N,N-dimethylaminobut-2-ene nitrile and carbonyl derivatives.

In the presence of boron trifluoride etherate, 2,3-bis(trimethylsilylmethyl)-1,3-butadiene reacts with aldehydes and ketones to lead generally to an only product, resulting from an hetero Diels-Alder reaction.

Some ω-functional propargylic-bis-trimethylsilanes, easily prepared from propargyltrimethylsilane through classical methods, allow a convenient one-pot synthesis of 2-alkyl-4-trimethylsilyl-3-vinylidenetetrahydropyranes and N-alkyl-4-trimethylsilyl-3-vinylidene-piperidines. These new silanes undergo a protodesilylation reaction leading to conjugated heterocyclic dienes.

Functionalisation of β or γ carboxyl group of aspartic and glutamic acids with labile substituents was performed via the use of N-trichloroethoxycarbonyl5-oxazolidinone as protective group.

The preparation of some α-iminoesters R′NCHCOOCH 3 with R′ bearing an alcohol group has been studied; organozinc compounds prepared from allylic or propargylic bromides and from α-bromoesters or α-bromoamides react regiospecifically with these α-iminoesters to give polyfunctional α-aminoesters. Some of them are easily converted into tetrahydro-1,4-oxazin-2-ones and hexahydro-1,4-oxazepin-2-ones.

The preparation of some α-iminoesters R′NCHCOO-t-C4H9 with R′ bearing an alcohol group has been studied; organozinc compounds prepared from allylic or propargylic bromides and from α-bromoesters or α-bromoamides react regiospecifically with these α-iminoesters to give polyfunctional α-aminoesters.

Pinacol-E-1-trimethylsilyl-1-propene-3-boronate regiospecifically reacts with aldimines and ketimines to lead to 4-amino-3-trimethylsilylalk-1-enes with good yields.

N-alkylaminomethylphosphonates were prepared in a one-pot Mannich-type reaction from monosily-lated primary amines, aliphatic aldehydes or ketones and diethyl phosphite HP(O) (OC2H5)2.

The one-pot synthesis of 1-allyl-1-cyano-1-alkenes is easily obtained from 1-allyl-1-trimethylsilylacetonitrile lithium and carbonyl derivatives via a silyl-Wittig-Peterson reaction. Other related compounds are prepared in the same manner.

In the presence of boron trifluoride etherate, 2,3-bis(trimethylsilylmethyl)-1,3-butadiene reacts with aldehydes and ketones to lead generally to an only product, resulting from an hetero Diels-Alder reaction.

The one-pot synthesis of 2-cyano-4-N,N-dimethylaminobut-2-en-1-ols is easily obtained by using allylic lithioanion prepared from 4-N,N-dimethylaminobut-2-ene nitrile and carbonyl derivatives.

The reaction between Grignard reagents prepared from allylic or propargylic halides and the N-phenylsulfenimine derived from the heptane-2,6-dione affords primary 1-alkenyl (or alkynyl)-3-methylcyclohex-2-enamines in good yields.

The 2-trimethylsilyl-2,3-butadienal is easily prepared, in good yield, by the reaction at −80°C between triethylorthoformate and the organoaluminum compound prepared from Me3SiCC-CH2Br. The resulting conjugated aldehyde reacts readily with various organometallic compounds (containing Al, Mg, Zn) to produce alcohols resulting from an 1,2-addition only, but for the saturated or phenylic magnesium derivatives which also give products from 1,4-addition.

The one-pot synthesis of 1-allyl-1-cyano-1-alkenes is easily obtained from 1-allyl-1-trimethylsilylacetonitrile lithium and carbonyl derivatives via a silyl-Wittig-Peterson reaction. Other related compounds are prepared in the same manner.

(2E, 4E)-1,6-bistrimethylsilylhexa-2,4-diene is a very convenient reagent to prepare in a one-pot reaction, from aldehydes or activated ketones, in the presence of a Lewis acid, either oxolanes with two vinylic substituents or homopentadienylic β-functional silanes.

The organozinc prepared from trimethylsilylpropargylbromide regiospecifically reacts with triple bond of monosubstituted α-accetylenic alcohols, ethers, amines and bromides, to lead to functional 1-trimethylsilyl-4-en-1-ynes in good yield. These derivatives are easily desilylated to produce functional 1-en-4-ynes.

The one-pot synthesis of α-branched β-alcynyl primary amines results from reaction between organometallic compounds, prepared from propargylic bromides and N-silylimines derived from aromatic or aliphatic aldehydes. Usually, the reaction is regioselective, but not in the case of CH3CCCH2M.

Lithiated trimethylsilylacetonitrile easily reacts, at −78°C, with various alkyl bromides to lead to α-functional trimethylsilanes RCH(SiMe3)CN, with R a saturated or unsaturated group.

In many cases, the reaction between α- or ω-chloro carbonyl derivatives and organoaluminium compound prepared from Me3Si−CC−CH2Br is chemo- and regioselective: it affords, in a good yield, trimethylsiyl α′ - or μ′-substituted by a chlorine atom; some of these functional alcohols have produced oxygenated heterocycles.

N-alkylaminomethylphosphonates were prepared in a one-pot Mannich-type reaction from monosily-lated primary amines, aliphatic aldehydes or ketones and diethyl phosphite HP(O) (OC2H5)2.

A convenient one-pot synthesis of alkynylsilanes bearing a cyclic ether group is described.