Could not get unknown property 'classpath' for object of type org.gradle.api.internal.artifacts.dsl.dependencies.DefaultDependencyHandler

I'm building Ionic app to Android device. My gradle version is 3.3. I'm a first timer to this Android building. I got following error:

Build file 'E:\FarmApp\smartFarm\platforms\android\build.gradle' line: 33

    * What went wrong:
    A problem occurred evaluating root project 'android'.
    > Could not get unknown property 'classpath' for object of type
    org.gradle.api.internal.artifacts.dsl.dependencies.DefaultDependencyHandler.

My build.gradle file section follows

 buildscript {
repositories {
    mavenCentral()
    jcenter()
}

// Switch the Android Gradle plugin version requirement depending on the
// installed version of Gradle. This dependency is documented at
// http://tools.android.com/tech-docs/new-build-system/version-compatibility
// and https://issues.apache.org/jira/browse/CB-8143
dependencies {
    classpath 'com.android.tools.build:gradle:2.2.3',
    classpath 'com.google.gms:google-services:3.1.0'
}
}

 // Allow plugins to declare Maven dependencies via build-extras.gradle.
allprojects {
repositories {
    mavenCentral();
    jcenter()
  }
 }

task wrapper(type: Wrapper) {
gradleVersion = '2.14.1'
}